[CentOS-docs] Images for CentOS Documentation
I'm currently porting the public and free parts of Red Hat Documentation to CentOS. Being unable to do anything graphics-related, I need someone to provide the following images: logo.svg300x140 CentOS Logo image_left.png 124x39 CentOS Logo image_right.png 120x41 CentOS Documentation Logo (to be designed) Thank you! Regards, Andreas -- Solvention Ltd. Co. KG Egermannstr. 6-8 53359 Rheinbach Tel: +49 2226 158179-0 Fax: +49 2226 158179-9 http://www.solvention.de mailto:i...@solvention.de ___ CentOS-docs mailing list CentOS-docs@centos.org http://lists.centos.org/mailman/listinfo/centos-docs
Re: [CentOS-es] CONEXION VNC
-Original Message- From: centos-es-boun...@centos.org [mailto:centos-es-boun...@centos.org] On Behalf Of Carlos Alberto Jara Alva Sent: Wednesday, March 02, 2011 10:03 AM To: centos-es@centos.org Subject: [CentOS-es] CONEXION VNC Saludos comunidad, tengo un problema, tengo instalado un centos 5.4 en mi servidor, todo esta muy bien, pero necesito asesoria porque queremos administrarlo de forma remota desde otro ladoes decir tratar de ingresar desde cualquier punto del planeta tierra a dicho servidor usando VNC, que es lo que necesito para configurarlo?? el modelo del router es trendnet tew - 657BRM, donde modifico algo? Gracias Abre exclusivamente el puerto 22, y adminístralo por via de comando. Usar VNC, o NX u lo que sea grafico, es un desperdicio de recursos, tanto de maquina, como de ancho de banda. Si aun asi, insistes, pues configura openvpn, para que tengas acceso encriptado, levanta tu vnc y pon xrdp. Desde cualquier Windows con el cliente de openvpn podras conectarte y no ocupas instalar nada, puesto que puedes usar el cliente de escritorio remoto. Saludos ___ CentOS-es mailing list CentOS-es@centos.org http://lists.centos.org/mailman/listinfo/centos-es
Re: [CentOS] Gnu Screen - terminal issues
On Thu, Mar 03, 2011 at 03:49:37PM -0800, Dr. Ed Morbius wrote: I meant to note earlier: the upstream NX developers have gone non-free, no? https://secure.wikimedia.org/wikipedia/en/wiki/NX_technology#License Is there a free software development branch? Presumably the freenx developers will fork the 3.x branch, but this relies on NoMachine continuing to distribute a 3.x-compatible client. If they cease distributing the older client, the freenx-server folks will have difficulties. Some other alternatives, references from the above wikipedia page: http://code.google.com/p/neatx/ (no client?) http://code.google.com/p/partiwm/wiki/xpra (not a remote desktop, but at least GPL) --keith -- kkel...@wombat.san-francisco.ca.us pgpdMeF5aujKq.pgp Description: PGP signature ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
[CentOS] Xen stack scheme
I need to restructure my server farm from tower PC:s to a minimal amount of 1U rack servers. I am going to rely on xen virtualization, as KVM seems not to be very mature yet. My current problem is the mail server, which uses a lot of CPU and I/O. A dedicated machine would be the best option. But would there be any sense in this: - run the mail server in xen dom0 (to get full native performance) - append a couple of light-weight servers as domU:s (like name server) - Jussi Hirvi -- Jussi Hirvi * Green Spot Topeliuksenkatu 15 C * 00250 Helsinki * Finland Tel. +358 9 493 981 * Mobile +358 40 771 2098 (only sms) jussi.hi...@greenspot.fi * http://www.greenspot.fi ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
[CentOS] Migrating standalone systems to xen guests
Is there any (easy?) way to migrate running standalone CentOS 4 or 5 systems to xen virtual stacks? Rebuilding those systems from scratch on the xen machine would take plenty of work. - Jussi Hirvi ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] HOW to REDIRECT to HTTPS?
On 03/03/2011 08:04 AM erikmccaskey64 wrote: I'm searching for a method [on client side] to redirect to HTTPS in a few given domains. e.g.: http://www.facebook.com/ to https://www.facebook.com/ Ok. I use several webbrowsers, and not all of them has add-ons to redirect these pages to https. My purpose is this: when i go to http://www.facebook.com; i don't want to see any http traffic with wireshark Is this possible?? How can i achieve it? How can i automatically redirect http traffic for given domain names to HTTPS?? Someone else already mention https-everywhere, the firefox plug-in. That works for me. eff.org recently had an extensive article on this very topic. You may want to search their site for more info. ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Migrating standalone systems to xen guests
Is there any (easy?) way to migrate running standalone CentOS 4 or 5 systems to xen virtual stacks? Rebuilding those systems from scratch on the xen machine would take plenty of work. I did so but it can be a bit tricky. You need to make sure you have the needed kernel installed and also configured disk modules and mount points and such. Then you can use tar or rsync to migrate the whole system. Maybe you can install one guest just for test and see how exactly it must be configured. Then you configure the live systems the same way. I can't tell you exactly because it's long time ago - and it's not really easy :) Simon ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Xen stack scheme
I need to restructure my server farm from tower PC:s to a minimal amount of 1U rack servers. I am going to rely on xen virtualization, as KVM seems not to be very mature yet. My current problem is the mail server, which uses a lot of CPU and I/O. A dedicated machine would be the best option. But would there be any sense in this: - run the mail server in xen dom0 (to get full native performance) - append a couple of light-weight servers as domU:s (like name server) I don't know if it's recommended that way but at least it works fine. Simon ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
[CentOS] kernel vulnerabilities
Hello, I am using CentOS 5.5 I planned to update the kernel rpm because of vulnerabilities came out lately. The new redhat updated kernel would be 2.6.18-238.5.1.el5 Also Scientific Linux did and update to the kernels according to redhat advisories but I have seen that CentOS is still bound to kernel 2.6.18-194.32.1.el5 so no security update is available. I was wondering if this is normal or not. thank you Riccardo ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Xen stack scheme
On 4.3.2011 10.52, Simon Matter wrote: I don't know if it's recommended that way but at least it works fine. Hm, that is kind of the only important thing. :-) If it is not recommended, there have to be better reasons for that than mere tidiness. - Jussi ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
[CentOS] kernel NETDEV WATCHDOG: eth0: transmit timed out
Hi , all : Sometimes my server network connection on Linux goes down with short message in syslog saying: [localhost kernel] NETDEV WATCHDOG: eth0: transmit timed out (or similar). By the way , I installed the CentOS 5.4 x86_64 bit and the kernel version was 2.6.18-164. Has anyone experienced this problem or is it the bug of the kernel ? I restart the network and that problem have resolved just now. ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] kernel NETDEV WATCHDOG: eth0: transmit timed out
Hi , all : Sometimes my server network connection on Linux goes down with short message in syslog saying: [localhost kernel] NETDEV WATCHDOG: eth0: transmit timed out (or similar). By the way , I installed the CentOS 5.4 x86_64 bit and the kernel version was 2.6.18-164. Has anyone experienced this problem or is it the bug of the kernel ? It usually happens with problems on the physical layer. You network card may be bad, or the connection, or the other side of the ethernet wire, or a driver problem in the linux kernel. We don't have enough information from you so say more. Simon ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Xen stack scheme
On Fri, Mar 04, 2011 at 11:11:52AM +0200, Jussi Hirvi wrote: On 4.3.2011 10.52, Simon Matter wrote: I don't know if it's recommended that way but at least it works fine. Hm, that is kind of the only important thing. :-) If it is not recommended, there have to be better reasons for that than mere tidiness. Dom0 should be reserved only for management toolstack and minimal amount of services (storage/network backends). Actually dom0 is a *VM* aswell (see xm list), although it has more direct access to the hardware and thus to storage. You're probably limited by the disk IOPS anyway, so it shouldn't matter that much if you run the service in dom0 or in domU, so go for domU, since that's the more safe bet. -- Pasi ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Migrating standalone systems to xen guests
On Fri, Mar 04, 2011 at 10:31:18AM +0200, Jussi Hirvi wrote: Is there any (easy?) way to migrate running standalone CentOS 4 or 5 systems to xen virtual stacks? Rebuilding those systems from scratch on the xen machine would take plenty of work. If you're talking about Xen PV domUs, then the process is pretty much like this: - ssh into the standalone system. - make sure /etc/modprobe.conf includes xenblk driver (so that it'll be included in the generated initrd when you install kernel-xen). - fix /etc/fstab to have xvd* (xen virtual disk) devices instead of sd*. - install kernel-xen rpm. - verify kernel-xen is the default in /boot/grub/grub.conf. - verify root= parameter is correct in /boot/grub/grub.conf for kernel-xen. - copy/transfer all the files from the standalone system to virtual disk/image. - create a configuration file for the new domU, make it use pygrub bootloader, and make it use xvd* disks/devices. - done. -- Pasi ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Migrating standalone systems to xen guests
On Fri, Mar 04, 2011 at 10:31:18AM +0200, Jussi Hirvi wrote: Is there any (easy?) way to migrate running standalone CentOS 4 or 5 systems to xen virtual stacks? Rebuilding those systems from scratch on the xen machine would take plenty of work. If you're talking about Xen PV domUs, then the process is pretty much like this: - ssh into the standalone system. - make sure /etc/modprobe.conf includes xenblk driver (so that it'll be included in the generated initrd when you install kernel-xen). - fix /etc/fstab to have xvd* (xen virtual disk) devices instead of sd*. - install kernel-xen rpm. - verify kernel-xen is the default in /boot/grub/grub.conf. - verify root= parameter is correct in /boot/grub/grub.conf for kernel-xen. - copy/transfer all the files from the standalone system to virtual disk/image. Make sure here to copy with preserving hardlinks, use tar or rsync -aH for this. And, you can exclude some content like /dev/* (but not the directory /dev itself!). - create a configuration file for the new domU, make it use pygrub bootloader, and make it use xvd* disks/devices. Also, you may have to adjust network config. - done. And, if something goes wrong, you can simply loop mount the filesystem on the Xen host and fix things, maybe chrooting before depending on what you do. Simon ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Migrating standalone systems to xen guests
On 4.3.2011 11.42, Pasi Kärkkäinen wrote: is pretty much like this: - ssh into the standalone system. Ok, thanks - that looks like a real how-to already. I will have to consider if I want to take the risk. With name server I would not bother, but with mail server maybe. - Jussi ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] kernel vulnerabilities
the archive would have told you. Kai ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Xen stack scheme
On Fri, Mar 04, 2011 at 11:37:08AM +0200, Pasi Kärkkäinen wrote: On Fri, Mar 04, 2011 at 11:11:52AM +0200, Jussi Hirvi wrote: On 4.3.2011 10.52, Simon Matter wrote: I don't know if it's recommended that way but at least it works fine. Hm, that is kind of the only important thing. :-) If it is not recommended, there have to be better reasons for that than mere tidiness. Dom0 should be reserved only for management toolstack and minimal amount of services (storage/network backends). Actually dom0 is a *VM* aswell (see xm list), although it has more direct access to the hardware and thus to storage. You're probably limited by the disk IOPS anyway, so it shouldn't matter that much if you run the service in dom0 or in domU, so go for domU, since that's the more safe bet. Oh, you should also limit and dedicate fixed amount of memory for dom0, say, 768 MB, or whatever you need there. http://wiki.xensource.com/xenwiki/XenBestPractices -- Pasi ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Centos 6 - What are you looking forward to?
On 03/03/2011 11:44 PM, Jimmy Bradley wrote: I do have one question about Cent OS 6. Sonetimes back, I remember reading that the plan was to spread the iso's over multiple cd's, rather than put it all on 1 dvd. Is that still the plan? As far as when it's released, I say take all the time you need. I'd rather have an os that works, than something that's just thrown together, and is about as stable as windows me, or vista. That will depend upon how upstream wrote the item that splits the RPMs. The distros are getting so big now that it might not make sense to continue to create CDs ... CentOS 5.6 will have at least 8 (and maybe 9) CDs for x86_64. I would expect that number to grow for CentOS 6. In fact, we already had to split 5.5 x86_64 over 2 DVDs, and both arches for CentOS 6 will likely be 2 DVDs. signature.asc Description: OpenPGP digital signature ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Migrating standalone systems to xen guests
On 03/04/2011 02:31 AM, Jussi Hirvi wrote: Is there any (easy?) way to migrate running standalone CentOS 4 or 5 systems to xen virtual stacks? Rebuilding those systems from scratch on the xen machine would take plenty of work. I think I would use KVM guests and not Xen guests ... but that is just me. KVM does not require a special kernel and is the supported solution in future versions of upstream products. signature.asc Description: OpenPGP digital signature ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Gnu Screen - terminal issues
On Fri, Mar 4, 2011 at 3:03 AM, Keith Keller kkel...@wombat.san-francisco.ca.us wrote: On Thu, Mar 03, 2011 at 03:49:37PM -0800, Dr. Ed Morbius wrote: I meant to note earlier: the upstream NX developers have gone non-free, no? https://secure.wikimedia.org/wikipedia/en/wiki/NX_technology#License Version 4, which is in beta, looks non free. We'll see what happens there. Is there a free software development branch? Presumably the freenx developers will fork the 3.x branch, but this relies on NoMachine continuing to distribute a 3.x-compatible client. If they cease distributing the older client, the freenx-server folks will have difficulties. Some other alternatives, references from the above wikipedia page: http://code.google.com/p/neatx/ (no client?) Neatx is entirely reliant on the nx toolkit, it's only python wrappers to get a server to work. I've personally written and submitted .spec files for it, and for various reasons just wrote a RHEL 6 .spec file for it. I can't recommend it. It's incomplete abandonware, nominally easier to set up than FreeNX (which is why someone I worked with wound up using it) but entirely unmaintained, and it has significant bugs with dead session, especially on reboot, and it lacks other useful features such as shared sessions. It's more abandonware. I'm afraid that for personal use, I'm recommending a test of the version 4 and consider using the free, though closed source, tools from the company that wrote the protocol, or buying licenses. http://code.google.com/p/partiwm/wiki/xpra (not a remote desktop, but at least GPL) Potentially useful for persistent X sessions, I see. If I didn't benefit from all the other features of NX (such as the bandwidth reduction and cheap/free and lightweight X server for Windows), I'd consider pursuing it. ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
[CentOS] Scientific Linux 6.0 released (based on RHEL 6.0)
I know this is the CentOS list. However, as there has been some interest in CentOS 6.0 (RHEL 6), I thought I'd share the news here. Scientific Linux 6 is based on RHEL 6 with add-ons for scientific computing. FWIW, the Admin tools etc. are pretty much the same as in RHEL, so are the base packages. Read more at http://www.scientificlinux.org/distributions/6x/60/ -- Arun Khan ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Scientific Linux 6.0 released (based on RHEL 6.0)
On 03/04/2011 01:33 PM, Arun Khan wrote:
I know this is the CentOS list. However, as there has been some
interest in CentOS 6.0 (RHEL 6), I thought I'd share the news here.
Scientific Linux 6 is based on RHEL 6 with add-ons for scientific computing.
FWIW, the Admin tools etc. are pretty much the same as in RHEL, so are
the base packages.
Read more at
http://www.scientificlinux.org/distributions/6x/60/
And?? Why do you want to start a new flame??
--
CL Martinez
carlopmart {at} gmail {d0t} com
___
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Re: [CentOS] Scientific Linux 6.0 released (based on RHEL 6.0)
On Fri, Mar 4, 2011 at 7:35 AM, carlopmart carlopm...@gmail.com wrote: On 03/04/2011 01:33 PM, Arun Khan wrote: I know this is the CentOS list. However, as there has been some interest in CentOS 6.0 (RHEL 6), I thought I'd share the news here. Scientific Linux 6 is based on RHEL 6 with add-ons for scientific computing. FWIW, the Admin tools etc. are pretty much the same as in RHEL, so are the base packages. Read more at http://www.scientificlinux.org/distributions/6x/60/ And?? Why do you want to start a new flame?? Now, now, be nice. It's nice to know if another open source knowledge has achieved a goal. It also provides an early testing platform for people who want to run some behavior comparisons. For example, the format of the kickstart file has changed in RHEL 6, and yum no longer installs both i386 and x86_64 components by default. It's a lot easier to get a handle on such changes if you can test them out early, even if CentOS 6 isn't available yet. ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Centos 6 - What are you looking forward to?
On Fri, Mar 4, 2011 at 6:33 AM, Johnny Hughes joh...@centos.org wrote: On 03/03/2011 11:44 PM, Jimmy Bradley wrote: I do have one question about Cent OS 6. Sonetimes back, I remember reading that the plan was to spread the iso's over multiple cd's, rather than put it all on 1 dvd. Is that still the plan? As far as when it's released, I say take all the time you need. I'd rather have an os that works, than something that's just thrown together, and is about as stable as windows me, or vista. That will depend upon how upstream wrote the item that splits the RPMs. The distros are getting so big now that it might not make sense to continue to create CDs ... CentOS 5.6 will have at least 8 (and maybe 9) CDs for x86_64. I would expect that number to grow for CentOS 6. In fact, we already had to split 5.5 x86_64 over 2 DVDs, and both arches for CentOS 6 will likely be 2 DVDs. And even the DVD's are hitting limits. The current RHEL 6 Server DVD does not contain python-docutils or audiofile-devel, they're part of a separate optional channel. (This just drove me insane trying to recompile nx and neatx, I was *very* surprised they weren't part of the basic channel.) CentOS doesn't maintain all these distinct channels they can just leave off of the installation media, so may face a size burden trying to get all those nominally other channel components onto one DVD, especially that optional channel. ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Centos 6
On Fri, Mar 4, 2011 at 12:42 AM, Eero Volotinen eero.voloti...@iki.fi wrote: 2011/2/28 JD jd1...@gmail.com: Any word on approximate release date of Centos 6? Cheers, Scientific Linux already released version 6. take it and then upgrade to centos, when it is available .. Re-install, not upgrade. Components with the same name compiled for different systems will occur, and may wind up presenting fascinating incompatibilities. I've written tools to turn an RHEL 5 box to CentOS 5, and back. It's a pain and I don't recommend it. ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Migrating standalone systems to xen guests
On Fri, Mar 4, 2011 at 4:57 AM, Simon Matter simon.mat...@invoca.ch wrote: On Fri, Mar 04, 2011 at 10:31:18AM +0200, Jussi Hirvi wrote: Is there any (easy?) way to migrate running standalone CentOS 4 or 5 systems to xen virtual stacks? Rebuilding those systems from scratch on the xen machine would take plenty of work. If you're talking about Xen PV domUs, then the process is pretty much like this: - ssh into the standalone system. - make sure /etc/modprobe.conf includes xenblk driver (so that it'll be included in the generated initrd when you install kernel-xen). - fix /etc/fstab to have xvd* (xen virtual disk) devices instead of sd*. - install kernel-xen rpm. - verify kernel-xen is the default in /boot/grub/grub.conf. - verify root= parameter is correct in /boot/grub/grub.conf for kernel-xen. - copy/transfer all the files from the standalone system to virtual disk/image. Make sure here to copy with preserving hardlinks, use tar or rsync -aH for this. And, you can exclude some content like /dev/* (but not the directory /dev itself!). Use star. This will preserve SELinux configurations, which neither tar nor rsync do. ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Scientific Linux 6.0 released (based on RHEL 6.0)
On Fri, Mar 4, 2011 at 6:14 PM, Nico Kadel-Garcia nka...@gmail.com wrote: On Fri, Mar 4, 2011 at 7:35 AM, carlopmart carlopm...@gmail.com wrote: And?? Why do you want to start a new flame?? That was certainly not the intent. Pls. see below. Now, now, be nice. It's nice to know if another open source knowledge has achieved a goal. It also provides an early testing platform for people who want to run some behavior comparisons. For example, the format of the kickstart file has changed in RHEL 6, and yum no longer installs both i386 and x86_64 components by default. It's a lot easier to get a handle on such changes if you can test them out early, even if CentOS 6 isn't available yet. Posted here for the motivations cited above and for those interested in getting an early start. I don't have access to a RHEL subscription. I use CentOS. I am going to use SL 6 to learn what is going to be new in CentOS 6. -- Arun Khan ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Centos 6 - What are you looking forward to?
On Fri, 4 Mar 2011, Nico Kadel-Garcia wrote: Contemporary versions of git, subversion, and OpenSSH built-in. I'm particularly looking forward to the built-in chroot capabilities and GSSAPI support in OpenSSH, and the major release improvements to git and subversion. What does the new GSSAPI support do for you? jh ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Migrating standalone systems to xen guests
On Fri, Mar 4, 2011 at 4:57 AM, Simon Matter simon.mat...@invoca.ch wrote: On Fri, Mar 04, 2011 at 10:31:18AM +0200, Jussi Hirvi wrote: Is there any (easy?) way to migrate running standalone CentOS 4 or 5 systems to xen virtual stacks? Rebuilding those systems from scratch on the xen machine would take plenty of work. If you're talking about Xen PV domUs, then the process is pretty much like this: - ssh into the standalone system. - make sure /etc/modprobe.conf includes xenblk driver (so that it'll be included in the generated initrd when you install kernel-xen). - fix /etc/fstab to have xvd* (xen virtual disk) devices instead of sd*. - install kernel-xen rpm. - verify kernel-xen is the default in /boot/grub/grub.conf. - verify root= parameter is correct in /boot/grub/grub.conf for kernel-xen. - copy/transfer all the files from the standalone system to virtual disk/image. Make sure here to copy with preserving hardlinks, use tar or rsync -aH for this. And, you can exclude some content like /dev/* (but not the directory /dev itself!). Use star. This will preserve SELinux configurations, which neither tar nor rsync do. Ah, forgot about that, because I always disable SELinux - if I want it so secure I'd take OpenBSD :) Simon ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Scientific Linux 6.0 released (based on RHEL 6.0)
On Fri, Mar 04, 2011 at 07:44:46AM -0500, Nico Kadel-Garcia wrote: Now, now, be nice. It's nice to know if another open source knowledge has achieved a goal. It also provides an early testing platform for people who want to run some behavior comparisons. For example, the format of the kickstart file has changed in RHEL 6, and yum no longer installs both i386 and x86_64 components by default. It's a lot easier to get a handle on such changes if you can test them out early, even if CentOS 6 isn't available yet. You've been able to do such testing for ever and a day; RHEL 6 has a 30-day trial available for free. John -- All I ask is this: Do something. Try something. Speaking out, showing up, writing a letter, a check, a strongly worded e-mail. Pick a cause -- there are few unworthy ones. And nudge yourself past the brink of tacit support to action. Once a month, once a year, or just once. -- Joss Whedon (1964-), writer and film director pgpfN64KA5qEK.pgp Description: PGP signature ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Centos 6 - What are you looking forward to?
Nico Kadel-Garcia wrote: On Thu, Mar 3, 2011 at 10:11 AM, Digimer li...@alteeve.com wrote: How about the rest of you? What are you looking forward to in CentOS 6 when it is released? Contemporary versions of git, subversion, and OpenSSH built-in. I'm particularly looking forward to the built-in chroot capabilities and GSSAPI support in OpenSSH, and the major release improvements to git and subversion. Minor point, but RHEL 5.6 finally bumped subversion to 1.6.X, so at least we'll see that in CentOS 5.6 too. -Greg ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Centos 6
Am 04.03.2011 13:50, schrieb Nico Kadel-Garcia: Re-install, not upgrade. Components with the same name compiled for different systems will occur, and may wind up presenting fascinating incompatibilities. Can you elaborate? RHEL5's and C5's packages were known to be interchangeable. Without having tried it RHEL6/SL6 this is FUD. I've written tools to turn an RHEL 5 box to CentOS 5, and back. It's a pain and I don't recommend it. For how many boxes do you need to do this? I did this with some boxes and never run into issues. Rainer ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Centos 6
robert mena wrote: Well, I am just telling that since there is no actual schedule, no plans to change the way things are handled (lack of communication, treat this as personal project etc) the best way to simply forget about it. The solution is good now and will be good whenever it appears. So there snip Actually, it strikes me that I *do* have a question: what are the main problems in the build/release? Has RH deliberately obscured some part(s) of its build process, or made prerequisites utterly dependent upon specific versions of libraries - that is, more than y'all have had to deal with before? Note that this is a question about the problemss, *not* about how y'all are going about it, nor whining that I Want It Yesterday!!! As someone who spent a lot of years as a developer (and let's not talk about the death march at a former Baby Bell), I like to know the kinds of problems that are ongoing, so I can get some feel for what's going on. mark sorry, no time to do some of the real work, RL is overwhelming at the moment ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Centos 6 - What are you looking forward to?
On 3/4/11 5:33 AM, Johnny Hughes wrote: On 03/03/2011 11:44 PM, Jimmy Bradley wrote: I do have one question about Cent OS 6. Sonetimes back, I remember reading that the plan was to spread the iso's over multiple cd's, rather than put it all on 1 dvd. Is that still the plan? As far as when it's released, I say take all the time you need. I'd rather have an os that works, than something that's just thrown together, and is about as stable as windows me, or vista. That will depend upon how upstream wrote the item that splits the RPMs. The distros are getting so big now that it might not make sense to continue to create CDs ... CentOS 5.6 will have at least 8 (and maybe 9) CDs for x86_64. I would expect that number to grow for CentOS 6. In fact, we already had to split 5.5 x86_64 over 2 DVDs, and both arches for CentOS 6 will likely be 2 DVDs. I always liked the way you could NFS-install from a directory containing the downloaded CD iso images but I could never get that to work with a dvd iso. Is there an equally easy way to install from a DVD image on a box without a DVD drive? -- Les Mikesell lesmikes...@gmail.com ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Centos 6
On 03/04/2011 08:42 AM, m.r...@5-cent.us wrote: robert mena wrote: Well, I am just telling that since there is no actual schedule, no plans to change the way things are handled (lack of communication, treat this as personal project etc) the best way to simply forget about it. The solution is good now and will be good whenever it appears. So there snip Actually, it strikes me that I *do* have a question: what are the main problems in the build/release? Has RH deliberately obscured some part(s) of its build process, or made prerequisites utterly dependent upon specific versions of libraries - that is, more than y'all have had to deal with before? Note that this is a question about the problemss, *not* about how y'all are going about it, nor whining that I Want It Yesterday!!! As someone who spent a lot of years as a developer (and let's not talk about the death march at a former Baby Bell), I like to know the kinds of problems that are ongoing, so I can get some feel for what's going on. mark sorry, no time to do some of the real work, RL is overwhelming at the moment ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos I saw this posted yesterday on h-online.com. http://www.h-online.com/open/news/item/Controversy-surrounds-Red-Hat-s-obfuscated-source-code-release-1200554.html ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Centos 6 - What are you looking forward to?
Greetings, On 3/4/11, Les Mikesell lesmikes...@gmail.com wrote: I always liked the way you could NFS-install from a directory containing the downloaded CD iso images but I could never get that to work with a dvd iso. Is there an equally easy way to install from a DVD image on a box without a DVD drive? dunno if mount -o loopback DVD.ISOPath and the point shared over nfs works. Regards, Rajagopal ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Load balancing...
aurfal...@gmail.com wrote: On Mar 3, 2011, at 3:43 PM, Todd wrote: Can anyone help me hash out how best to load balance a website that is getting considerable traffic? In the past I only have experience with BigIP where you have a load balancing device that keeps track and send traffic to the best server possible at the time. This was a proprietary system that I think was something Dell rebranded. Right now, the whole site is is 400gb of video, HTML5, Apache, PHP, MySQL, runs on a single box with 16gb of RAM and mirrored /var/www/ html (2x1tb raid level drives). I have a Comcast 50/10 connection, 5 statics and I am seeing about 125 unique visitors a day. The site runs fine, but in anticipation of more traffic as well as a learning experience I would like to load balance. snip What about a dedicated load balancing device? What specs should this snip If you're talking a load-balancing appliance, they get pricey. When I was at ATT a few years ago, for a small group, we got one from Radware (a competitor of F5, the Big Name), but it was still several thousand dollars. It worked quite well, btw (and if you are interested, I can contact the vendor engineer I worked with) A warning: round robin can be problematical. At the same job, before we got the Radware box, we were going through IBM's WebSeal (part of the Tivoli suite). We went to upgrade one of four boxes from a perl website to php... and then discovered that the stupid thing did *not* do persistant connections, so someone would get (3 times out of 4) the perl, then it would 404 the next time, because it got the php, or vice versa. mark ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Centos 6 - What are you looking forward to?
On 3/4/11 5:33 AM, Johnny Hughes wrote: On 03/03/2011 11:44 PM, Jimmy Bradley wrote: I do have one question about Cent OS 6. Sonetimes back, I remember reading that the plan was to spread the iso's over multiple cd's, rather than put it all on 1 dvd. Is that still the plan? As far as when it's released, I say take all the time you need. I'd rather have an os that works, than something that's just thrown together, and is about as stable as windows me, or vista. That will depend upon how upstream wrote the item that splits the RPMs. The distros are getting so big now that it might not make sense to continue to create CDs ... CentOS 5.6 will have at least 8 (and maybe 9) CDs for x86_64. I would expect that number to grow for CentOS 6. In fact, we already had to split 5.5 x86_64 over 2 DVDs, and both arches for CentOS 6 will likely be 2 DVDs. I always liked the way you could NFS-install from a directory containing the downloaded CD iso images but I could never get that to work with a dvd iso. Is there an equally easy way to install from a DVD image on a box without a DVD drive? Yes, it's still possible, but needs a little bit more work. In the directory where the DVD ISO is, you have to create a directory called images and put the install.img file from the ISO there: [someone@ftp x86_64]$ ll -R .: total 3953768 drwxr-xr-x 2 root root 4096 Nov 12 15:25 images -rw-r--r-- 1 root root210 Nov 12 12:31 MD5SUMS -rw-r--r-- 1 root root 232761344 Oct 26 03:16 rhel-server-6.0-x86_64-boot.iso -rw-r--r-- 1 root root 3431618560 Oct 26 19:09 rhel-server-6.0-x86_64-dvd.iso -rw-r--r-- 1 root root 380297216 Nov 4 21:48 rhel-server-supplementary-6.0-x86_64-dvd.iso ./images: total 119780 -r--r--r-- 1 root root 122527744 Sep 23 00:04 install.img Regards, Simon ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] kernel NETDEV WATCHDOG: eth0: transmit timed out
sync wrote: Sometimes my server network connection on Linux goes down with short message in syslog saying: [localhost kernel] NETDEV WATCHDOG: eth0: transmit timed out (or similar). By the way , I installed the CentOS 5.4 x86_64 bit and the kernel version was 2.6.18-164. Has anyone experienced this problem or is it the bug of the kernel ? I restart the network and that problem have resolved just now. How are you connecting to the 'Net? Is this a commercial line, or only, say, DSL? mark, just fought the good fight with Verizon over the latter ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Gnu Screen - terminal issues
On 3/4/11 12:15 AM, Dr. Ed Morbius wrote: I do like the way gnome collapses the icons in the task bar when you have enough of them - and pops up the list so you can see it. It makes it easy to find the terminal session connected to some particular remote host. WindowMaker has a windowlist. Even better. I usually last 1-4 hours when I periodically try GNOME. KDE and XFCE I might last a few days. Then it's back to the One True Window Manager. I don't care about the mechanism so much as having everything I do on one screen, under one window manager. So all of my terminal sessions collapse in one place that becomes a popup list. Likewise all of my firefox windows (and for this reason I like separate windows better than tabs). I'm really just fine with terminal windows and SSH-forwarded apps if those are necessary. But why do you need screen, then? Terminal multiplexing, session persistance, scrollback/logging, split screen (top running in the top panel, shell underneath, etc.), workflow organization (similar processes are grouped in a screen session). But all of that just happens by itself in a GUI screen and isn't limited to text mode. I'm writing this mail in mutt, in a screen session with multiple mailboxes open, each to its own screen window. It's like a multi-tabbed GNOME or KDE terminal, except that the session persists even if the controlling terminal is killed, or X dies altogether. Yes, but you are limited to text mode apps. I actually have a GUI session that persists even if my local connection breaks. And it performs pretty well when I pick it up remotely. And I can't recall a time when the server side of the X connection ever died. Screen is one of those amazingly powerful Linux tools, once you stumble across it. But NX/freenx does the same and more. The only down side I can see is the time for the initial screen draw over a slow connection. -- Les Mikesell lesmikes...@gmail.com ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] kernel NETDEV WATCHDOG: eth0: transmit timed out
On Friday, March 04, 2011 10:18:53 am sync wrote: Hi , all : Sometimes my server network connection on Linux goes down with short message in syslog saying: [localhost kernel] NETDEV WATCHDOG: eth0: transmit timed out (or similar). By the way , I installed the CentOS 5.4 x86_64 bit and the kernel version was 2.6.18-164. 5.4 w/o updates is 1) (more) buggy and insecure 2) behind on driver versions. That's one general and on specific reason for you to type yum update (preferably before you invest too much time investigating this hw/driver problem). /Peter Has anyone experienced this problem or is it the bug of the kernel ? I restart the network and that problem have resolved just now. signature.asc Description: This is a digitally signed message part. ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Centos 6
On 03/04/2011 08:42 AM, m.r...@5-cent.us wrote: robert mena wrote: Well, I am just telling that since there is no actual schedule, no plans to change the way things are handled (lack of communication, treat this as personal project etc) the best way to simply forget about it. The solution is good now and will be good whenever it appears. So there snip Actually, it strikes me that I *do* have a question: what are the main problems in the build/release? Has RH deliberately obscured some part(s) of its build process, or made prerequisites utterly dependent upon specific versions of libraries - that is, more than y'all have had to deal with before? Note that this is a question about the problemss, *not* about how y'all are going about it, nor whining that I Want It Yesterday!!! As someone who spent a lot of years as a developer (and let's not talk about the death march at a former Baby Bell), I like to know the kinds of problems that are ongoing, so I can get some feel for what's going on. mark sorry, no time to do some of the real work, RL is overwhelming at the moment ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos I saw this posted yesterday on h-online.com. http://www.h-online.com/open/news/item/Controversy-surrounds-Red-Hat-s-obfuscated-source-code-release-1200554.html I don't think it makes the work for CentOS harder, why should it? The CentOS kernel are 99.9% the same like RedHat's kernel, only very little changes are made to the src package (it may affect the centosplus kernels, but not the main one I guess). Simon ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Centos 6
Jason Brown wrote: On 03/04/2011 08:42 AM, m.r...@5-cent.us wrote: robert mena wrote: Well, I am just telling that since there is no actual schedule, no plans to change the way things are handled (lack of communication, treat this as personal project etc) the best way to simply forget about it. The solution is good now and will be good whenever it appears. So there snip Actually, it strikes me that I *do* have a question: what are the main problems in the build/release? Has RH deliberately obscured some part(s) of its build process, or made prerequisites utterly dependent upon specific versions of libraries - that is, more than y'all have had to deal with before? Note that this is a question about the problemss, *not* about how y'all are going about it, nor whining that I Want It Yesterday!!! As someone who spent a lot of years as a developer (and let's not talk about the death march at a former Baby Bell), I like to know the kinds of problems that are ongoing, so I can get some feel for what's going on. mark sorry, no time to do some of the real work, RL is overwhelming at the moment ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos I saw this posted yesterday on h-online.com. http://www.h-online.com/open/news/item/Controversy-surrounds-Red-Hat-s-obfuscated-source-code-release-1200554.html Once again Oracle business practices screw it up for the rest of the world. ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos attachment: rkampen.vcf___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Centos 6
Jason Brown wrote: On 03/04/2011 08:42 AM, m.r...@5-cent.us wrote: robert mena wrote: Well, I am just telling that since there is no actual schedule, no plans to change the way things are handled (lack of communication, treat this as personal project etc) the best way to simply forget about it. The solution is good now and will be good whenever it appears. So snip Actually, it strikes me that I *do* have a question: what are the main problems in the build/release? Has RH deliberately obscured some part(s) of its build process, or made prerequisites utterly dependent upon specific versions of libraries - that is, more than y'all have had to deal with before? snip I saw this posted yesterday on h-online.com. http://www.h-online.com/open/news/item/Controversy-surrounds-Red-Hat-s-obfuscated-source-code-release-1200554.html Don't know h-online, but that's *real* interesting, and explains a lot: not us, but Them (Oracle). Having had my recent experience with Oracle (which I posted here a month or so ago), I can understand why they don't want to help them mark ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Scientific Linux 6.0 released (based on RHEL 6.0)
Anyway, this was an information by the OP and by itself ok, although I guess everybody already knew it. But please try to refrain from making it another longwinding thread. Not aimed at anyone particular, you are just the last in the thread I have here. Thanks :-) Kai ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Gnu Screen - terminal issues
On Mar 3, 2011, at 17:50, Les Mikesell wrote: I almost never log in directly at a linux console anymore and if I need to do something from home or remotely, I just pick the session that was my last desktop at work. I didn't know you could do this with NX. I've been using VNC to connect to my session at work from home, but it's kinda slow. So how do you use NX technology to connect to an *existing* GUI session (in my case Gnome if that matters)? Sorry, I know this is off topic, but then again this entire thread seems to be headed off on a tangent... Alfred ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Centos 6 - What are you looking forward to?
On Fri, Mar 04, 2011 at 05:33:20AM -0600, Johnny Hughes wrote: On 03/03/2011 11:44 PM, Jimmy Bradley wrote: I do have one question about Cent OS 6. Sonetimes back, I remember reading that the plan was to spread the iso's over multiple cd's, rather than put it all on 1 dvd. Is that still the plan? As far as when it's released, I say take all the time you need. I'd rather have an os that works, than something that's just thrown together, and is about as stable as windows me, or vista. That will depend upon how upstream wrote the item that splits the RPMs. The distros are getting so big now that it might not make sense to continue to create CDs ... CentOS 5.6 will have at least 8 (and maybe 9) CDs for x86_64. I would expect that number to grow for CentOS 6. In fact, we already had to split 5.5 x86_64 over 2 DVDs, and both arches for CentOS 6 will likely be 2 DVDs. How reasonable would it be to offer DVD images that fit on DL media? I know I don't own any DL media, and probably most others don't either, but I at least do have DL-capable optical drives. If a good enough reason came up, e.g., my favorite distro making DL isos available, I'd probably go buy some. -- Fred Smith -- fre...@fcshome.stoneham.ma.us - For the word of God is living and active. Sharper than any double-edged sword, it penetrates even to dividing soul and spirit, joints and marrow; it judges the thoughts and attitudes of the heart. Hebrews 4:12 (niv) -- ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Load balancing...
On Thu, Mar 3, 2011 at 6:43 PM, Todd slackmoehrle.li...@gmail.com wrote: Hi All, Can anyone help me hash out how best to load balance a website that is getting considerable traffic? In the past I only have experience with BigIP where you have a load balancing device that keeps track and send traffic to the best server possible at the time. This was a proprietary system that I think was something Dell rebranded. Right now, the whole site is is 400gb of video, HTML5, Apache, PHP, MySQL, runs on a single box with 16gb of RAM and mirrored /var/www/html (2x1tb raid level drives). I have a Comcast 50/10 connection, 5 statics and I am seeing about 125 unique visitors a day. The site runs fine, but in anticipation of more traffic as well as a learning experience I would like to load balance. Obviously I need a second server just like the one it is running on now. I will probably spec something out that is capable of 32gb of RAM. What about a dedicated load balancing device? What specs should this be? How much RAM, HD, processor? It is sufficient to buy something with a GB NIC and say 4gb of RAM? Can one go slower but more RAM, small HD? I don't really quite know how intensive a task this decision making process is for the load balancer.. Right now, as example, I have an Untangle Firewall and it runs on a old AMD with 2gb RAM, GB NIC and it seems to do just fine. My local computer store has several P4 2.8ghz with 2GB of RAM for like $99 Can anyone enlighten me on specs, proper setup, caveats? -Jason You have a lot of issues here, and some unanswered questions. Is the load on your site mostly bandwidth use? Do you have users who need to login to a system? Is the application designed to run with multiple front-ends? It's easy to get very basic load balancing, but your app most likely will require sticky sessions to ensure the user goes to the same backend server every time, and many solutions don't have this feature. Of the free options already listed, here are the problems with them: - Round Robin DNS: Provides no additional features other then very poor load spreading across servers. As soon as you talk about load balancing there are usually features you need that this cannot provide, like automatic failover, dynamic adding/removing hosts, etc... Sticky sessions are simply not possible. RR DNS should not be used except in extremely basic situations. - Linux LVS: This is a good idea on the face of it, but it can open up some tricky issues with routing and IP address handling. Also, sticky sessions are based on subnet of the IP address, which for many corporations using proxies will not work. I have seen companies that spread their proxy load across multiple /8 networks, so there's no way to sticky them. OK, so what's good? For my requirements, HAProxy is excellent. It handled sticky sessions well, performs monitoring of each host, allows dynamic adding/removing of servers, as well as maintenance modes. It's very easy to install and configure. I'm using is as the backend to apache that is acting as an SSL termination point. It's been very high performing for us and I know a lot of big sites use it as well. The only question I would have with it is handling of video, as we only use it for typical web traffic, just high bandwidth stuff like that. Also, make sure any load balancer you have is redundant and has some kind of failover, using something like pacemaker, heartbeat, etc... ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] RFC: video call recommendations
On Wed, March 2, 2011 17:57, b.j. mcclure wrote: +1 for Skype on CentOS 5.5, RHEL 6, and various flavors of Ubuntu. B.J. CentOS 5.5, Linux 2.6.18-194.32.1.el5 athlon 17:56:31 up 13 days, 22:24, 1 user, load average: 0.67, 0.53, 0.43 So, how did you install Skype on CentOS-5.5? I tried using the Fedora rpm but got a failed dependency, on qt-4 I think. -- *** E-Mail is NOT a SECURE channel *** James B. Byrnemailto:byrn...@harte-lyne.ca Harte Lyne Limited http://www.harte-lyne.ca 9 Brockley Drive vox: +1 905 561 1241 Hamilton, Ontario fax: +1 905 561 0757 Canada L8E 3C3 ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Gnu Screen - terminal issues
In this case, you might want to conditionally assign some reasonable value on failure. Say: tput -T $TERM init /dev/null 21 || export TERM=xterm 'tset -q' is another test which can be used. The remote host's $TERM variable is in fact xterm. When I connect to the screen session the $TERM variable is 'screen'. I think it's because I'm opening a new ssh session in each screen window. Not a huge deal; I mainly use this for short commands, and if I need to run something longer I just write it all out in a text editor and paste it into the terminal. ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] virtualization on the desktop a myth, or a reality?
On Thursday, March 03, 2011 06:55:56 pm Dr. Ed Morbius wrote: I thought a bit about that when posting earlier. I still disagree WRT dual-booting. And no, virtualization doesn't need twice the hardware by a long shot (aggregated load averaging, shared componentry, and a host of other savings). It needs twice the CPU and twice the RAM to work in a reliable manner for professional low-latency audio production. The DSP in Harrison Mixbus alone needs one whole CPU core pretty much dedicated to it alone; and that's just the DSP engine, and doesn't count the Ardour-based user interface; two cores is a minimum requirement to run Mixbus, as stated clearly on Harrison's website, and as verified independently by myself and others. Otherwise you get xruns, and xruns kill your quality. Not to mention the fact that the GTK GUI goes into erratic comas when you try to single-core it (even with a very fast core this is the case). Don't get me wrong; I have tried this with virtualization; it simply does not work at the latencies required when the track count gets higher. It just doesn't work; xruns will find their way into the audio. And that's on both the host and the guest; guest load can cause the host to xrun. They are after all still sharing the same bus or PCIe fabric, and high track counts at low latency already heavily stress the PCI bus and 1x PCIe lanes, for the audio interface and for the disks; do the bandwidth calculation for yourself for 32 tracks at 96kHz sampling at 24 bits from the audio interface and 32-bit floating point to the disk. And that's bidirectional. So if I'm running two instances of Mixbus, I need a minimum of four cores, and the memory balloon driver that's typically part of the guest's virtualization tools package can cause more problems that it's worth (I'm fighting this now with CentOS 4 (32-bit) under VMware ESX 3.5U5 on a server; I'm getting oom-killer hitting (typically it takes out clamscan, one of the antivirus engines I'm running on that server) after a couple of weeks of uptime, and after eight to twelve hours of oom-killer hitting, the root filesystem goes read-only and a hard reboot of the guest is required to recover; once I get some data on why, I'm going to file a bug report, since it started about two months ago after a long time of reliable uptime; perhaps a kernel or a glibc or a clamav (not in the CentOS repositories, third-party) update destabilized something, but I don't have enough data to be helpful yet). Audio's pretty easy, as you could select between sources and output (or input) accordingly. Low-latency audio isn't easy on Linux even on bare metal; I'm talking low-latency audio, where you're overdubbing material and need sub-50ms delay between inputs and outputs. I'm running a Tascam US-224 and a US-428 in the special raw USB mode and have achieved 11ms latencies, but that isn't easy. The preemptive kernel is required for this, and accurate timekeeping is required for this; you even have to turn off CPU frequency scaling to get it to work correctly as the latency goes down. And the audio latency has to be consistent; one reason pulseaudio is typically tossed out completely and JACK is the audio server of choice. And I'm not talking about a small number of ins and outs; with RME Hammerfall equipment and outboard converters you could easily have 32 or more tracks in and that many out running concurrently. You could have Ardour/Mixbus running 40 tracks with 8 or 16 or more recording while the others are playing in an overdub session, and latency must be hard-realtime controlled (otherwise the performers doing the overdub are going to strangle the engineer). Since the DSP plugins are running in real-time as well, you end up with quite a load, and it has to be hard realtime when you get to that many tracks. CentOS is used quite heavily in these circumstances, incidentally, because of the history of reliability and solid version stability; the hard part becomes getting newer versions of software running. The other application I thought about last night is NTP stratum 1 and 2 disciplined clocks where the 1pps output from a GPS receiver is used along with the timecode coming down the serial. I have yet to find any virtualization solution that keeps well enough time to be an NTP server at all, much less stratum 1 or 2. ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Centos 6
On Wed, March 2, 2011 20:43, Johnny Hughes wrote: Do you think we are not trying or damnedest to get it done as fast as we possibly can? What, exactly, is the problem here? The problem here is fear. I am not now asking, nor to the best of my ability to recall have I ever asked, for when a particular version of CentOS will be made available. I have nothing but admiration for those who contribute meaningfully to producing something that I value highly, including the folks at RedHat. Nor do I feel that the CentOS project is in trouble. On the other hand, the first indication that a project is in trouble is usually prolonged and unexpected delay in getting the next anticipated release out. As that time drags on the anxiety level of those who have committed themselves, and their companies, to a project naturally rises. Most of us take these things with more than a grain of salt. We have seen it before and we will see it again. I came to CentOS through through CAOS which I came to from WhiteBox. And, if the need arises, I will no doubt find acceptable alternatives to CentOS. But other may feel, sometimes with good reason, their competence questioned or job security threatened if their selection turns out to be a dead end. These people desire some sort of assurance that their choice will still prove correct however things appear now. That is what they are looking for. Their question, when will it be ready? is not really what they want answered. They are looking for assurance in a form that they can show others. A due date seems to satisfy that desire but something else, a schedule of milestones, a status report, that shows activity might well suffice. -- *** E-Mail is NOT a SECURE channel *** James B. Byrnemailto:byrn...@harte-lyne.ca Harte Lyne Limited http://www.harte-lyne.ca 9 Brockley Drive vox: +1 905 561 1241 Hamilton, Ontario fax: +1 905 561 0757 Canada L8E 3C3 ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Scientific Linux 6.0 released (based on RHEL 6.0)
On 03/04/2011 07:35 AM, carlopmart wrote: On 03/04/2011 01:33 PM, Arun Khan wrote: I know this is the CentOS list. However, as there has been some interest in CentOS 6.0 (RHEL 6), I thought I'd share the news here. Scientific Linux 6 is based on RHEL 6 with add-ons for scientific computing. FWIW, the Admin tools etc. are pretty much the same as in RHEL, so are the base packages. Read more at http://www.scientificlinux.org/distributions/6x/60/ And?? Why do you want to start a new flame?? Pointing out the advancement of a similar product is legit, in my mind. We all need to relax. :) -- Digimer E-Mail: digi...@alteeve.com AN!Whitepapers: http://alteeve.com Node Assassin: http://nodeassassin.org ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Gnu Screen - terminal issues
On 3/4/2011 8:51 AM, Alfred von Campe wrote: On Mar 3, 2011, at 17:50, Les Mikesell wrote: I almost never log in directly at a linux console anymore and if I need to do something from home or remotely, I just pick the session that was my last desktop at work. I didn't know you could do this with NX. I've been using VNC to connect to my session at work from home, but it's kinda slow. So how do you use NX technology to connect to an *existing* GUI session (in my case Gnome if that matters)? Sorry, I know this is off topic, but then again this entire thread seems to be headed off on a tangent... Theoretically NX can do a 'shadow' session where the client connects to an existing current connection, and as a special case, this can be the console. However, I've had trouble getting those connections to work at all (I think the size and color depth has to match exactly or something) and when they do, they don't really perform any better than vnc anyway and you can't resize the desktop to match your local screen. So, the way to do it is to start the session under NX to begin with. There's some overhead if you do it on the local machine but except for playing video it shouldn't be enough to notice. But if you can run your session on a faster server box that is noisy enough that you don't want it at your desk - or you have a slow/cheap box at your desk, or move around to different machines, or need access to a different OS, it comes out as a win to run everything that way. In my case I generally park it filling one screen of a dual-headed windows box. And even those things don't apply for your main work, you might park a session on some well-connected machine that you can reach remotely through vpn or ssh. Then a single client connection to that gives you access to both whatever you left running there and all of the internal machines it can reach. -- Les Mikesell lesmikes...@gmail.com ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Load balancing...
OK, so what's good? For my requirements, HAProxy is excellent. It handled sticky sessions well, performs monitoring of each host, allows dynamic adding/removing of servers, as well as maintenance modes. It's very easy to install and configure. I'm using is as the backend to apache that is acting as an SSL termination point. It's been very high performing for us and I know a lot of big sites use it as well. The only question I would have with it is handling of video, as we only use it for typical web traffic, just high bandwidth stuff like that. Also, make sure any load balancer you have is redundant and has some kind of failover, using something like pacemaker, heartbeat, etc... I second the vote for HAProxy. It's one excellent free (as in beer) load balancer that is very easy to setup and configure. One big site that uses it is 37 signals (the makers of basecamp and campfire among other things). HAProxy is capable of handling a lot of traffic apparently. I use it with a shared docroot living on and NFS mount. Works really great! It balances two centos vm's as primary with a physical freebsd host acting as a fallback. Other good choices include nginx with the upstream fair plugin and #pound from apsis. http://www.apsis.ch/pound/ http://wiki.nginx.org/LoadBalanceExample Any of the above (pound, nginx or haproxy) will handle sticky sessions skillfully. As to hardware load balancers I think that Netscaler by citrix deserves an honorable mention: http://deliver.citrix.com/go/citrix/WWAD0111Q1NSGOOGLECLOUDWP?gclid=CNDzzIantacCFQFM5QodslJN_w But like any hardware lb they're certainly not cheap!! I remember when my last company was considering which load balancer to go with the contenders were Zeus, F5 and Citrix Netscaler. I think they're all good products, but I remember when the F5 salesman came by, part of his sales pitch was Ok, if you don't go with us I can understand why you would go with Netscaler. But Zeus? Really, guys? On Fri, Mar 4, 2011 at 10:09 AM, Brian Mathis brian.mat...@gmail.com wrote: On Thu, Mar 3, 2011 at 6:43 PM, Todd slackmoehrle.li...@gmail.com wrote: Hi All, Can anyone help me hash out how best to load balance a website that is getting considerable traffic? In the past I only have experience with BigIP where you have a load balancing device that keeps track and send traffic to the best server possible at the time. This was a proprietary system that I think was something Dell rebranded. Right now, the whole site is is 400gb of video, HTML5, Apache, PHP, MySQL, runs on a single box with 16gb of RAM and mirrored /var/www/html (2x1tb raid level drives). I have a Comcast 50/10 connection, 5 statics and I am seeing about 125 unique visitors a day. The site runs fine, but in anticipation of more traffic as well as a learning experience I would like to load balance. Obviously I need a second server just like the one it is running on now. I will probably spec something out that is capable of 32gb of RAM. What about a dedicated load balancing device? What specs should this be? How much RAM, HD, processor? It is sufficient to buy something with a GB NIC and say 4gb of RAM? Can one go slower but more RAM, small HD? I don't really quite know how intensive a task this decision making process is for the load balancer.. Right now, as example, I have an Untangle Firewall and it runs on a old AMD with 2gb RAM, GB NIC and it seems to do just fine. My local computer store has several P4 2.8ghz with 2GB of RAM for like $99 Can anyone enlighten me on specs, proper setup, caveats? -Jason You have a lot of issues here, and some unanswered questions. Is the load on your site mostly bandwidth use? Do you have users who need to login to a system? Is the application designed to run with multiple front-ends? It's easy to get very basic load balancing, but your app most likely will require sticky sessions to ensure the user goes to the same backend server every time, and many solutions don't have this feature. Of the free options already listed, here are the problems with them: - Round Robin DNS: Provides no additional features other then very poor load spreading across servers. As soon as you talk about load balancing there are usually features you need that this cannot provide, like automatic failover, dynamic adding/removing hosts, etc... Sticky sessions are simply not possible. RR DNS should not be used except in extremely basic situations. - Linux LVS: This is a good idea on the face of it, but it can open up some tricky issues with routing and IP address handling. Also, sticky sessions are based on subnet of the IP address, which for many corporations using proxies will not work. I have seen companies that spread their proxy load across multiple /8 networks, so there's no way to sticky them. OK, so what's good? For my requirements, HAProxy is excellent. It handled sticky sessions well, performs monitoring
Re: [CentOS] Load balancing...
also I forgot to mention for heartbeat I use keepalived http://www.keepalived.org/ I found hearbeat a little difficult to implement but keepalived by comparison is a breeze to setup. Forget about multiple A records. That's a naive approach and entirely unnecessary. As other's have pointed out just setup a virtual ip using keepalived (or heartbeat or maybe something similar) and point your A record to that virtual ip. On Fri, Mar 4, 2011 at 11:17 AM, Tim Dunphy bluethu...@gmail.com wrote: OK, so what's good? For my requirements, HAProxy is excellent. It handled sticky sessions well, performs monitoring of each host, allows dynamic adding/removing of servers, as well as maintenance modes. It's very easy to install and configure. I'm using is as the backend to apache that is acting as an SSL termination point. It's been very high performing for us and I know a lot of big sites use it as well. The only question I would have with it is handling of video, as we only use it for typical web traffic, just high bandwidth stuff like that. Also, make sure any load balancer you have is redundant and has some kind of failover, using something like pacemaker, heartbeat, etc... I second the vote for HAProxy. It's one excellent free (as in beer) load balancer that is very easy to setup and configure. One big site that uses it is 37 signals (the makers of basecamp and campfire among other things). HAProxy is capable of handling a lot of traffic apparently. I use it with a shared docroot living on and NFS mount. Works really great! It balances two centos vm's as primary with a physical freebsd host acting as a fallback. Other good choices include nginx with the upstream fair plugin and #pound from apsis. http://www.apsis.ch/pound/ http://wiki.nginx.org/LoadBalanceExample Any of the above (pound, nginx or haproxy) will handle sticky sessions skillfully. As to hardware load balancers I think that Netscaler by citrix deserves an honorable mention: http://deliver.citrix.com/go/citrix/WWAD0111Q1NSGOOGLECLOUDWP?gclid=CNDzzIantacCFQFM5QodslJN_w But like any hardware lb they're certainly not cheap!! I remember when my last company was considering which load balancer to go with the contenders were Zeus, F5 and Citrix Netscaler. I think they're all good products, but I remember when the F5 salesman came by, part of his sales pitch was Ok, if you don't go with us I can understand why you would go with Netscaler. But Zeus? Really, guys? On Fri, Mar 4, 2011 at 10:09 AM, Brian Mathis brian.mat...@gmail.com wrote: On Thu, Mar 3, 2011 at 6:43 PM, Todd slackmoehrle.li...@gmail.com wrote: Hi All, Can anyone help me hash out how best to load balance a website that is getting considerable traffic? In the past I only have experience with BigIP where you have a load balancing device that keeps track and send traffic to the best server possible at the time. This was a proprietary system that I think was something Dell rebranded. Right now, the whole site is is 400gb of video, HTML5, Apache, PHP, MySQL, runs on a single box with 16gb of RAM and mirrored /var/www/html (2x1tb raid level drives). I have a Comcast 50/10 connection, 5 statics and I am seeing about 125 unique visitors a day. The site runs fine, but in anticipation of more traffic as well as a learning experience I would like to load balance. Obviously I need a second server just like the one it is running on now. I will probably spec something out that is capable of 32gb of RAM. What about a dedicated load balancing device? What specs should this be? How much RAM, HD, processor? It is sufficient to buy something with a GB NIC and say 4gb of RAM? Can one go slower but more RAM, small HD? I don't really quite know how intensive a task this decision making process is for the load balancer.. Right now, as example, I have an Untangle Firewall and it runs on a old AMD with 2gb RAM, GB NIC and it seems to do just fine. My local computer store has several P4 2.8ghz with 2GB of RAM for like $99 Can anyone enlighten me on specs, proper setup, caveats? -Jason You have a lot of issues here, and some unanswered questions. Is the load on your site mostly bandwidth use? Do you have users who need to login to a system? Is the application designed to run with multiple front-ends? It's easy to get very basic load balancing, but your app most likely will require sticky sessions to ensure the user goes to the same backend server every time, and many solutions don't have this feature. Of the free options already listed, here are the problems with them: - Round Robin DNS: Provides no additional features other then very poor load spreading across servers. As soon as you talk about load balancing there are usually features you need that this cannot provide, like automatic failover, dynamic adding/removing hosts, etc... Sticky sessions are simply not possible. RR DNS should not be used except in
Re: [CentOS] HOW to REDIRECT to HTTPS?
erikmccaskey64 wrote: I'm searching for a method [on client side] to redirect to HTTPS in a few given domains. Is this a browser issue? If so then I know that Firefox has at least two plugins that can be configured to force https on links to certain domains or subdomains. On is NoScript, which is what we use. I cannot recall the name of the other but no doubt a search of the Firefox add-ons will find it. -- *** E-Mail is NOT a SECURE channel *** James B. Byrnemailto:byrn...@harte-lyne.ca Harte Lyne Limited http://www.harte-lyne.ca 9 Brockley Drive vox: +1 905 561 1241 Hamilton, Ontario fax: +1 905 561 0757 Canada L8E 3C3 ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
[CentOS] CentOS-announce Digest, Vol 73, Issue 2
Send CentOS-announce mailing list submissions to centos-annou...@centos.org To subscribe or unsubscribe via the World Wide Web, visit http://lists.centos.org/mailman/listinfo/centos-announce or, via email, send a message with subject or body 'help' to centos-announce-requ...@centos.org You can reach the person managing the list at centos-announce-ow...@centos.org When replying, please edit your Subject line so it is more specific than Re: Contents of CentOS-announce digest... Today's Topics: 1. CESA-2011:0219 Low CentOS 4 i386 and x86_64 EOL Notice (Johnny Hughes) -- Message: 1 Date: Thu, 03 Mar 2011 19:53:46 -0600 From: Johnny Hughes joh...@centos.org Subject: [CentOS-announce] CESA-2011:0219 Low CentOS 4 i386 and x86_64 EOL Notice To: CentOS-Announce centos-annou...@centos.org Message-ID: 4d70462a.9060...@centos.org Content-Type: text/plain; charset=iso-8859-1 CentOS Errata and Security Advisory CESA-2011:0219 This is the 1 year notification for the End of Life for the CentOS 4 distribution. The upstream provider will discontinue public updates of their EL4 product on February 29th, 2012. The CentOS Project will end support for CentOS 4 on the same date. CentOS 4, as well as all previously released versions of CentOS, will continue to be available in the Centos Vault: http://vault.centos.org/ This CESA includes a new centos-release file that reminds you of the February 29th, 2012 end of life date. Users still running production workloads on CentOS 4 are advised to begin planning the upgrade to CentOS 5 or (when available) CentOS 6 before the EOL date. For users who are unable to migrate off the EL 4 code base before its end-of-life date, the upstream provider intends to offer a limited, optional extension program. The CentOS Project recommends that you contact their sales team for a price quote for their extended service if you can not move to a newer code base before February 29th, 2012. x86_64: centos-release-4-9.1.x86_64.rpm i386: centos-release-4-9.1.i386.rpm src: centos-release-4-9.1.src.rpm -- next part -- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 253 bytes Desc: OpenPGP digital signature Url : http://lists.centos.org/pipermail/centos-announce/attachments/20110303/d042f60a/attachment-0001.bin -- ___ CentOS-announce mailing list centos-annou...@centos.org http://lists.centos.org/mailman/listinfo/centos-announce End of CentOS-announce Digest, Vol 73, Issue 2 ** ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Scientific Linux 6.0 released (based on RHEL 6.0)
On 04/03/11 16:59, Digimer wrote: On 03/04/2011 07:35 AM, carlopmart wrote: On 03/04/2011 01:33 PM, Arun Khan wrote: I know this is the CentOS list. However, as there has been some interest in CentOS 6.0 (RHEL 6), I thought I'd share the news here. Scientific Linux 6 is based on RHEL 6 with add-ons for scientific computing. FWIW, the Admin tools etc. are pretty much the same as in RHEL, so are the base packages. Read more at http://www.scientificlinux.org/distributions/6x/60/ And?? Why do you want to start a new flame?? Pointing out the advancement of a similar product is legit, in my mind. We all need to relax. :) +1 kind regards, David Sommerseth ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Xen stack scheme
On Fri, 4 Mar 2011, Jussi Hirvi wrote: I need to restructure my server farm from tower PC:s to a minimal amount of 1U rack servers. I am going to rely on xen virtualization, as KVM seems not to be very mature yet. What part of KVM seems immature to you? I deploy public-facing machines using both it and Xen, and I can't really speak to any difference in performance or small-scall management. -- Paul Heinlein heinl...@madboa.com http://www.madboa.com/ ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Xen stack scheme
What part of KVM seems immature to you? I deploy public-facing machines using both it and Xen, and I can't really speak to any difference in performance or small-scall management. I like kvm - no issues ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Centos 6
centos-boun...@centos.org wrote: On Wed, March 2, 2011 20:43, Johnny Hughes wrote: Do you think we are not trying or damnedest to get it done as fast as we possibly can? What, exactly, is the problem here? The problem here is fear. Your fear is not shared by me, in the least. And, if the need arises, I will no doubt find acceptable alternatives to CentOS. RHEL and Scientific Linux come to mind. So does *assisting* rather than *handwringing* about CentOS. But other may feel, sometimes with good reason, their competence questioned or job security threatened if their selection turns out to be a dead end. This is *speculating* about a reasonable basis of fear on the parts of Anonymous Others. These people desire some sort of assurance that their choice will still prove correct however things appear now. That is what they are looking for. The choice is a free alternative packaging of RHEL. Make that choice, and you're in the good. Johnny: Killfile the thread, we (loyalists) got you covered. Insert spiffy .sig here //me *** This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error please notify the system manager. This footnote also confirms that this email message has been swept for the presence of computer viruses. www.Hubbell.com - Hubbell Incorporated** ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Load balancing...
Brian, Thanks for all of the great words here. I appreciate the detail in your reply. OK, so what's good? For my requirements, HAProxy is excellent. It handled sticky sessions well, performs monitoring of each host, allows dynamic adding/removing of servers, as well as maintenance modes. It's very easy to install and configure. I'm using is as the backend to apache that is acting as an SSL termination point. It's been very high performing for us and I know a lot of big sites use it as well. The only question I would have with it is handling of video, as we only use it for typical web traffic, just high bandwidth stuff like that. Also, make sure any load balancer you have is redundant and has some kind of failover, using something like pacemaker, heartbeat, etc... Can you outline a bit specs for building a homemade box to run HAProxy? The HAProxy site is very extensive, but I did not see ideal specs at a quick glance. I will read in depth this weekend. Minimal specs and they excellent specs if you have thoughts.. I really don't have an idea how intensive a task like this is. Nobody needs to log into the box, simply use the box for this purpose. -Jason ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Scientific Linux 6.0 released (based on RHEL 6.0)
David Sommerseth wrote: On 04/03/11 16:59, Digimer wrote: On 03/04/2011 07:35 AM, carlopmart wrote: On 03/04/2011 01:33 PM, Arun Khan wrote: I know this is the CentOS list. However, as there has been some interest in CentOS 6.0 (RHEL 6), I thought I'd share the news here. Scientific Linux 6 is based on RHEL 6 with add-ons for scientific computing. snip Read more at http://www.scientificlinux.org/distributions/6x/60/ And?? Why do you want to start a new flame?? Pointing out the advancement of a similar product is legit, in my mind. We all need to relax. :) Actually, given that they're performing the same task as the CentOS team, and IMO the CentOS team is as good as the SL team, I take that to indicate that CentOS 6 is fairly close. mark, *not* looking forward to a major upgrade of all these machines ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Scientific Linux 6.0 released (based on RHEL 6.0)
On 03/04/2011 12:40 PM, m.r...@5-cent.us wrote: mark, *not* looking forward to a major upgrade of all these machines Heh, neither am I. 5.5 is trucking along just fine on many though, so I don't expect to actually rebuild many. I'll probably roll out new machines as CentOS 6 once I finish some internal testing, then just slowly start migrating services to them and rebuilding old ones as needed. I'm in no particular rush to move off of 5.x, but I am quite interested in seeing how smoothly I can add CentOS 6 machines to a cluster, migrate VMs to those nodes and then phase out the RL5 nodes. Should be fun! :D -- Digimer E-Mail: digi...@alteeve.com AN!Whitepapers: http://alteeve.com Node Assassin: http://nodeassassin.org ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Centos 6
On Wed, March 2, 2011 20:43, Johnny Hughes wrote: Do you think we are not trying or damnedest to get it done as fast as we possibly can? What, exactly, is the problem here? The problem here is fear. I am not now asking, nor to the best of my ability to recall have I ever asked, for when a particular version of CentOS will be made available. I have nothing but admiration for those who contribute meaningfully to producing something that I value highly, including the folks at RedHat. Nor do I feel that the CentOS project is in trouble. On the other hand, the first indication that a project is in trouble is usually prolonged and unexpected delay in getting the next anticipated release out. As that time drags on the anxiety level of those who have committed themselves, and their companies, to a project naturally rises. Most of us take these things with more than a grain of salt. We have seen it before and we will see it again. I came to CentOS through through CAOS which I came to from WhiteBox. And, if the need arises, I will no doubt find acceptable alternatives to CentOS. I'm not sure that's true. You have to understand that at the same time everybody should have worked on EL6.0, both EL5.6 and EL4.9 came out and for very good reason those responsible for CentOS decided to build those first. Just remember, the folks doing SL have been a bit faster with 6.0, but they did IIRC not do the 5.6 nor the 4.9 yet (maybe they rebuilt some packages to still be secure, but I think they didn't finish the full distribution). So, I'm quite sure it's not as bad as you think. Simon ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Gnu Screen - terminal issues
on 08:15 Fri 04 Mar, Les Mikesell (lesmikes...@gmail.com) wrote: On 3/4/11 12:15 AM, Dr. Ed Morbius wrote: But why do you need screen, then? Terminal multiplexing, session persistance, scrollback/logging, split screen (top running in the top panel, shell underneath, etc.), workflow organization (similar processes are grouped in a screen session). But all of that just happens by itself in a GUI screen and isn't limited to text mode. I think you're fundamentally failing to understand my operating mode. Local system == Linux === my administrative center. Remote hosts. May be a dozen. May be 20,000. Or some number between or beyond. Desktop persistance is local. If I have to interactively operate on an individual remote host, I'm doing my job wrong. Preferably that's limited to initial provisioning and possibly hardware troubleshooting. Ideally, not even then (I haven't met my ideal). I'm really not particularly interested in having some complex GUI state on multiple remote systems. Again: my objective isn't to change your mind but possibly open it a tad. That appears to be increasingly unlikely. I'm writing this mail in mutt, in a screen session with multiple mailboxes open, each to its own screen window. It's like a multi-tabbed GNOME or KDE terminal, except that the session persists even if the controlling terminal is killed, or X dies altogether. Yes, but you are limited to text mode apps. Feature. Running remote GUI management apps is an utter fail. If you've *GOT* to run some remote GUI application, then yes, you're going to want a tool that supports it, of which there are several, and of which NX is merely one of many options. It's not a best, standard, open, free, or actively developed (in free software) solution. I'm done here. -- Dr. Ed Morbius, Chief Scientist /| Robot Wrangler / Staff Psychologist| When you seek unlimited power Krell Power Systems Unlimited| Go to Krell! ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Gnu Screen - terminal issues
on 09:10 Fri 04 Mar, Sean Carolan (scaro...@gmail.com) wrote: In this case, you might want to conditionally assign some reasonable value on failure. Say: tput -T $TERM init /dev/null 21 || export TERM=xterm 'tset -q' is another test which can be used. The remote host's $TERM variable is in fact xterm. When I connect to the screen session the $TERM variable is 'screen'. Are you running screen locally or remotely? My experience is it's best to launch SSH sessions in their own terminal(s), then start screen on the remote side. This also generally provides more utility (you want a single session to a host, and a logically grouped set of shells / processes on that host). Nesting screen sesssions is possible, but generally not terribly friendly due to having to hit multiple C-a escapes for screen commands. I think it's because I'm opening a new ssh session in each screen window. Not a huge deal; I mainly use this for short commands, and if I need to run something longer I just write it all out in a text editor and paste it into the terminal. Or you could write a script, scp it to the hosts you want to run it on (testing first, natch), and exec it: for host in hostlist; do scp myscript $host:.; done [fiddle around with tests or verification as necessary] for host in hostlist; do echo ** $host **; ssh $host ./myscript; done ... which is a shell idiom that shows up a LOT in my history. As I mentioned earlier, dsh (distributed ssh) is a very powerful tool for running multiple remote commands. Puppet, cfengine, and other tools may also be useful. Scales from low multiples through thousands and more of hosts. -- Dr. Ed Morbius, Chief Scientist /| Robot Wrangler / Staff Psychologist| When you seek unlimited power Krell Power Systems Unlimited| Go to Krell! ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Gnu Screen - terminal issues
On 3/4/2011 8:15 AM, Les Mikesell wrote: I do like the way gnome collapses the icons in the task bar when you have enough of them - and pops up the list so you can see it. It makes it easy to find the terminal session connected to some particular remote host. WindowMaker has a windowlist. Even better. I usually last 1-4 hours when I periodically try GNOME. KDE and XFCE I might last a few days. Then it's back to the One True Window Manager. I don't care about the mechanism so much as having everything I do on one screen, under one window manager. So all of my terminal sessions collapse in one place that becomes a popup list. Likewise all of my firefox windows (and for this reason I like separate windows better than tabs). The reason I like this might not be clear if you don't use Gnome much. It's a combination of the way gnome-terminal puts usr@host:/path in the window title bar and keeps it updated when you ssh to compatible systems, and the way the Gnome desktop collapses many task bar items into one for each application when enough are open at once. I end up with a 'Gnome-terminal (count)' task bar item that when clicked pops up the list of window titles making it easy to go back to anywhere I already have a connection by yanking that screen to the front. Firefox does the same by putting the page names in the collapsed list which is easier to use than tabs within a screen. -- Les Mikesell lesmikes...@gmail.com ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] virtualization on the desktop a myth, or a reality?
On 03/03/11 00:41, Ross Walker wrote: [...snip...] This works with Xen or KVM, though the management and compartmentalization of Xen helps. Does CentOS support the shared memory pages, memory dedup, in Xen? That would allow for a lot more Linux VMs. I don't think the KSM support has been backported to the RHEL5/CentOS5 kernels. I might remember wrong though. _If_ KSM is available on the 2.6.18 based kernels, it should definitely work for KVM on RHEL5/CentOS5. However, I doubt it has been backported to the Xen dom0 kernels. If I've understood it correctly, the Xen hypervisor is its own microkernel and dom0 is kind of a virtual guest with more privileges than domUs, to be able to administer and control the guests. IIRC, this micro kernel got its own scheduler and memory management too. While with KVM, the host kernel (which loads the kvm.ko module) is the hypervisor, and all the virtual guests are qemu-kvm user space processes. And KSM will merge same pages for user space processes, no matter if it is KVM guests or other applications. kind regards, David Sommerseth ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Centos 6 - What are you looking forward to?
--On Thursday, March 03, 2011 10:11 AM -0500 Digimer li...@alteeve.com wrote: How about the rest of you? What are you looking forward to in CentOS 6 when it is released? A new Ruby so I can deploy a Diaspora pod for my friends, allowing them to escape Facebook. (I tried building Ruby from Rawhide but the dependencies soon went deep, too deep for a simple, isolated update.) ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Centos 6 - What are you looking forward to?
On Mar 4, 2011, at 11:07 AM, Kenneth Porter wrote: --On Thursday, March 03, 2011 10:11 AM -0500 Digimer li...@alteeve.com wrote: How about the rest of you? What are you looking forward to in CentOS 6 when it is released? A new Ruby +1 Having issues installing Earth; http://open.rsp.com.au/projects/earth - aurf ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
[CentOS] Updating hardware clock from cron
Is there a package to do this? Normally the hardware clock is set during shutdown if one is running ntpd. But if a long-running server shuts down unexpectedly, this isn't done, and the hardware clock might be off by a lot when it comes back up. So setting it periodically from a cron job could be useful. What do others do? Adding a one liner to /etc/cron.daily that invokes /etc/rc.d/init.d/ntpd would do it but it seems heavyweight to restart ntpd. Alas, the script doesn't export just the sync_hwclock function. ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Load balancing...
On Fri, Mar 4, 2011 at 9:34 AM, Todd slackmoehrle.li...@gmail.com wrote: Brian, Thanks for all of the great words here. I appreciate the detail in your reply. OK, so what's good? For my requirements, HAProxy is excellent. It handled sticky sessions well, performs monitoring of each host, allows dynamic adding/removing of servers, as well as maintenance modes. It's very easy to install and configure. I'm using is as the backend to apache that is acting as an SSL termination point. It's been very high performing for us and I know a lot of big sites use it as well. The only question I would have with it is handling of video, as we only use it for typical web traffic, just high bandwidth stuff like that. Also, make sure any load balancer you have is redundant and has some kind of failover, using something like pacemaker, heartbeat, etc... Can you outline a bit specs for building a homemade box to run HAProxy? The HAProxy site is very extensive, but I did not see ideal specs at a quick glance. I will read in depth this weekend. Minimal specs and they excellent specs if you have thoughts.. I really don't have an idea how intensive a task like this is. Nobody needs to log into the box, simply use the box for this purpose. -Jason ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos You want two boxes that run both haproxy + keepalived. This way you get the load balancing (HAProxy) plus the high availability (Keepalived) using a shared virtual IP for your two boxes. You can do maintenance on either one while traffic still remains active. I don't have metrics to spec out the boxes, but given your traffic load you mentioned you don't need hefty boxes at all. Just get yourself a box with some Gigabit interfaces which I'm sure they all are these days. A single socket with 4 cores is more than enough. You can probably even do with 2 cores. Someone can correct me on that if they think the solution requires a lot of CPU. Memory wise I think machines come with at least 4Gb these days. That should do. You can probably both boxes for around 2k? You already know how much F5 or any of those guys cost per device. =) Best, -- James H. Nguyen CallFire :: Systems Architect http://www.callfire.com 1.949.625.4263 ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Centos 6 - What are you looking forward to?
On Fri, Mar 04, 2011 at 11:12:45AM -0800, aurfal...@gmail.com wrote: Having issues installing Earth; /earth is 98% full ... please delete anyone you can. -- fortune file -- rgds Stephen ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Gnu Screen - terminal issues
On 3/4/2011 12:07 PM, Dr. Ed Morbius wrote: But why do you need screen, then? Terminal multiplexing, session persistance, scrollback/logging, split screen (top running in the top panel, shell underneath, etc.), workflow organization (similar processes are grouped in a screen session). But all of that just happens by itself in a GUI screen and isn't limited to text mode. I think you're fundamentally failing to understand my operating mode. Local system == Linux === my administrative center. No, I've done things that way too. And I've had a linux box at my desk and can boot my laptop into it when I want. I just prefer NX with what looks exactly like a local linux desktop because when I'm at my desk it's essentially the same (minor plus for having windows on the same box, but I could run a separate computer if I wanted) - and when I'm remote I still have it all. Remote hosts. May be a dozen. May be 20,000. Or some number between or beyond. Same. Mine are clustered in a few locations though, so I normally have some strategically located ssh connections to run management scripts to local sets instead of directly from my desktop session. And if I need to connect to one from home, I'll grab my desktop screen and pick up from there. Desktop persistance is local. But my desktop includes my terminal windows and ssh connections. If I have to interactively operate on an individual remote host, I'm doing my job wrong. Preferably that's limited to initial provisioning and possibly hardware troubleshooting. Ideally, not even then (I haven't met my ideal). I'm really not particularly interested in having some complex GUI state on multiple remote systems. Agreed, but much of my development/testing is in a lab across the country. For a few things, like working in a GUI report writer, I run a separate NX session to a box there, but for text work, it is just ssh in another terminal window on my main desktop. Again: my objective isn't to change your mind but possibly open it a tad. That appears to be increasingly unlikely. It isn't like I've never worked in text mode before, or directly in a Linux X desktop without NX, so I don't see anything I need to be 'open' to. I'm just saying NX is better than all the other ways I've tried. If you don't care about letting programs run essentially forever on your desktop or being able to continue work-in-progress from other places, fine, but no, you aren't going to convince me I don't like it. I'm writing this mail in mutt, in a screen session with multiple mailboxes open, each to its own screen window. It's like a multi-tabbed GNOME or KDE terminal, except that the session persists even if the controlling terminal is killed, or X dies altogether. Yes, but you are limited to text mode apps. Feature. No accounting for taste, I guess. I'll take thunderbird over mutt anytime, although that's an exception to my normal operating mode because I tend to run that on the local OS/screen instead of on the NX desktop. My accounts are all IMAP on a server reachable from the internet so there's no need to maintain a local state and thunderbird works more or less the same regardless of the OS. But that's just a practical matter of sometimes wanting email without the Linux desktop. Running remote GUI management apps is an utter fail. I'm agnostic about that. The only thing I depend on that you might call a GUI management tool is having firefox access to an assortment of monitoring, reporting, ticketing, etc. applications on the private side of the network. There are other ways this could be handled, but it is nice to just have already-open windows on the desktop that has access to everything. So if I'm connecting from home to work on some problem, I automatically have access to everything related including still-open monitor sessions, etc. You can do that with everything on a laptop but it's a lot harder to keep running sessions going while you drive home. If you've *GOT* to run some remote GUI application, then yes, you're going to want a tool that supports it, of which there are several, and of which NX is merely one of many options. It's not a best, standard, open, free, or actively developed (in free software) solution. The GUI apps mostly run on 'my' desktop without much concept of whether they are remote or not. I think that's the real difference in the way we are thinking. The text windows run there too - and they both run very nicely. The current NX client is free in the sense of cost and works with freenx. I've always wished that RAM had been cheap back when X was originally designed so that they would have put the proxy/cache that you need for performance in from the start, but as things stand, NX is as good as I've seen. If you think there is something better, cheaper, and standard that is equally functional, I'm very interested, but I'm not going back to mutt or screen or
Re: [CentOS] Load balancing...
James Nguyen wrote: On Fri, Mar 4, 2011 at 9:34 AM, Todd slackmoehrle.li...@gmail.com wrote: Brian, Thanks for all of the great words here. I appreciate the detail in your reply. OK, so what's good? For my requirements, HAProxy is excellent. It snip if they think the solution requires a lot of CPU. Memory wise I think machines come with at least 4Gb these days. That should do. You can probably both boxes for around 2k? You already know how much F5 or any of those guys cost per device. =) Hmmm... when the job I was at went with Radware, their price was significantly lower than F5, and I was impressed with the appliance. Nice little 1u box, not even a pizza box deep, as I recall. mark ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Load balancing...
On Fri, Mar 4, 2011 at 9:18 PM, James Nguyen ja...@callfire.com wrote: On Fri, Mar 4, 2011 at 9:34 AM, Todd slackmoehrle.li...@gmail.com wrote: Brian, Thanks for all of the great words here. I appreciate the detail in your reply. OK, so what's good? For my requirements, HAProxy is excellent. It handled sticky sessions well, performs monitoring of each host, allows dynamic adding/removing of servers, as well as maintenance modes. It's very easy to install and configure. I'm using is as the backend to apache that is acting as an SSL termination point. It's been very high performing for us and I know a lot of big sites use it as well. The only question I would have with it is handling of video, as we only use it for typical web traffic, just high bandwidth stuff like that. Also, make sure any load balancer you have is redundant and has some kind of failover, using something like pacemaker, heartbeat, etc... Can you outline a bit specs for building a homemade box to run HAProxy? The HAProxy site is very extensive, but I did not see ideal specs at a quick glance. I will read in depth this weekend. Minimal specs and they excellent specs if you have thoughts.. I really don't have an idea how intensive a task like this is. Nobody needs to log into the box, simply use the box for this purpose. -Jason ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos You want two boxes that run both haproxy + keepalived. This way you get the load balancing (HAProxy) plus the high availability (Keepalived) using a shared virtual IP for your two boxes. You can do maintenance on either one while traffic still remains active. I don't have metrics to spec out the boxes, but given your traffic load you mentioned you don't need hefty boxes at all. Just get yourself a box with some Gigabit interfaces which I'm sure they all are these days. A single socket with 4 cores is more than enough. You can probably even do with 2 cores. Someone can correct me on that if they think the solution requires a lot of CPU. Memory wise I think machines come with at least 4Gb these days. That should do. You can probably both boxes for around 2k? You already know how much F5 or any of those guys cost per device. =) Best, -- James H. Nguyen CallFire :: Systems Architect http://www.callfire.com 1.949.625.4263 ___ How well will this setup work as a load balancer for a couple of web servers, running cPanel / VirtualMin and a few hundred websites sharing the same IP on each server? -- Kind Regards Rudi Ahlers SoftDux Website: http://www.SoftDux.com Technical Blog: http://Blog.SoftDux.com Office: 087 805 9573 Cell: 082 554 7532 ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Load balancing...
On 3/4/2011 1:18 PM, James Nguyen wrote: You want two boxes that run both haproxy + keepalived. This way you get the load balancing (HAProxy) plus the high availability (Keepalived) using a shared virtual IP for your two boxes. You can do maintenance on either one while traffic still remains active. I don't have metrics to spec out the boxes, but given your traffic load you mentioned you don't need hefty boxes at all. Just get yourself a box with some Gigabit interfaces which I'm sure they all are these days. A single socket with 4 cores is more than enough. You can probably even do with 2 cores. Someone can correct me on that if they think the solution requires a lot of CPU. Memory wise I think machines come with at least 4Gb these days. That should do. You can probably both boxes for around 2k? You already know how much F5 or any of those guys cost per device. =) F5's are one of those things where if you have to ask the price you probably can't afford it... But they do provide a very nice web interface to control the pool members and virtual interfaces, something I haven't seen on free alternatives, and if you are big enough to have multiple locations they can propagate their server state info to their global DNS servers (also expensive) to control balancing/failover across sites. For a couple of boxes that can work independently, I'd just use round robin DNS and also use heartbeat to float the IP's to the backup on outages. That way you normally share the load for performance but if one fails or is shut down gracefully, the other one will still handle things for both IP targets. If your application maintains any session state you'll need to work out a way to keep it in sync or after the initial connection, redirect to a specific machine and live with what happens when it goes down (which might not be that bad, maybe just a new login when they try to come back). -- Les Mikesell lesmikes...@gmail.com ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Centos 6 - What are you looking forward to?
On Thu, Mar 3, 2011 at 10:11 AM, Digimer li...@alteeve.com wrote: Personally, I'm really looking forward to Cluster 3 support. It will be fun to see how Pacemaker compares to rgmanager. How about the rest of you? What are you looking forward to in CentOS 6 when it is released? I'm looking forward to the new cgroups and KVM. This will give it some capabilities similar to AIX virtual partitions which can divvy up CPUs at a fine resolution. Also, the new multipath configuration tools will make my life easier. ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Centos 6 - What are you looking forward to?
Kwan Lowe wrote: On Thu, Mar 3, 2011 at 10:11 AM, Digimer li...@alteeve.com wrote: Personally, I'm really looking forward to Cluster 3 support. It will be fun to see how Pacemaker compares to rgmanager. How about the rest of you? What are you looking forward to in CentOS 6 when it is released? I'm looking forward to the new cgroups and KVM. This will give it some capabilities similar to AIX virtual partitions which can divvy up CPUs at a fine resolution. Really? So IBM ported VM into native AIX? I missed that. mark ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Load balancing...
On Fri, Mar 4, 2011 at 11:25 AM, m.r...@5-cent.us wrote: James Nguyen wrote: On Fri, Mar 4, 2011 at 9:34 AM, Todd slackmoehrle.li...@gmail.com wrote: Brian, Thanks for all of the great words here. I appreciate the detail in your reply. OK, so what's good? For my requirements, HAProxy is excellent. It snip if they think the solution requires a lot of CPU. Memory wise I think machines come with at least 4Gb these days. That should do. You can probably both boxes for around 2k? You already know how much F5 or any of those guys cost per device. =) Hmmm... when the job I was at went with Radware, their price was significantly lower than F5, and I was impressed with the appliance. Nice little 1u box, not even a pizza box deep, as I recall. mark ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos Keep in mind you'd want at least 2 either it be appliances, devices or server boxes. The minimum for high availability is at least 2. That's assuming your power and internet route is already highly redundant as well. ;) -- James H. Nguyen CallFire :: Systems Architect http://www.callfire.com 1.949.625.4263 ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Updating hardware clock from cron
-Original Message- From: centos-boun...@centos.org [mailto:centos-boun...@centos.org] On Behalf Of Kenneth Porter Sent: Friday, March 04, 2011 14:15 To: CentOS mailing list Subject: [CentOS] Updating hardware clock from cron Is there a package to do this? Normally the hardware clock is set during shutdown if one is running ntpd. No, hwclock --systohc is only called at start time (in /etc/rc.d/init.d/ntpd), and only if ntpdate got a good time, which is a good thing. But if a long-running server shuts down unexpectedly, this isn't done, and the hardware clock might be off by a lot when it comes back up. Not if you are running ntp and it was able to sync, because ntpd activates a mode in the kernel that sets the hwclock every 11 minutes when ntp declares it got synced. If your hwclock is off by a lot when it comes up I believe it is from one of the following: A) bad cmos battery. B) poor cmos clock C) confusing info in /etc/adjtime due to using both hwclock --adjust [at boot] and ntp (long story, but it is due to both tweaking the clock without coordination between them). D) booting a different OS with different ideas of timezones. E) manual tweaking of time via bios. So setting it periodically from a cron job could be useful. What do others do? Adding a one liner to /etc/cron.daily that invokes /etc/rc.d/init.d/ntpd would do it but it seems heavyweight to restart ntpd. Alas, the script doesn't export just the sync_hwclock function. Recommendation, Understand `hwclock --systohc` should _only_ be called when the admin knows a good system time was *_JUST_* set from a good source, i.e., following a successful call to ntpdate or the admin setting the systime with date. On some systems that do NOT have ntpd service available (not on a network with a time server), I will have them do a sequence of hwclock --hctosys hwclock --adjust hwclock --hctosys in /etc/rc.d/rc.sysinit where it already does the hwclock --hctosys so that once I have set the time from a known source a few times the box will reasonably self correct time on boot, I will even on some of those systems have that sequence in a cronjob that gets run once a week. If this is on a network, I have the box that is doing this serve ntp (via local clock) to the rest of the network, so they drift together. Reminder: `hwclock --systohc` should _only_ be called when the admin knows system time was JUST set from a good source, i.e., NOT from a cron job that is not also making sure the ntpdate worked. ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Centos 6 - What are you looking forward to?
On 03/04/11 11:59 AM, m.r...@5-cent.us wrote: I'm looking forward to the new cgroups and KVM. This will give it some capabilities similar to AIX virtual partitions which can divvy up CPUs at a fine resolution. Really? So IBM ported VM into native AIX? I missed that. IBM Power servers since the Power4+ CPU (they are up to Power7 now) have hardware partitioning support, commonly known as LPAR. LPAR can be divided in units of 1/10th of a CPU. The software to manage this is now called PowerVM (its been called other names in the past, not all polite). In addition, AIX 6.1 and newer have Workload Partitions (WPAR), which are similar to Solaris Zones, these allow subdividing an AIX install into an arbitrary number of apparently different systems that all share the same kernel. LPAR plus VIOS (Virtual IO System, actually a stripped down preconfigured AIX system) corresponds to the Xen model, however the base hypervisor capability is built right into the CPU and IO hardware, VIOS just provides management and optional virtualized IO. You can assign IO adapters directly to partitions, whereupon the partitions (VMs) run even if VIOS is shut down. The newer Power6 and 7 servers have Ethernet adapters that provide each LPAR with its own hardware-virtualized ethernet adapter so you don't need a cage full of cards, or run all the networking through VIOS. ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Updating hardware clock from cron
the hardware clock might be off by a lot when it comes back up. If your server was set to use UTC time at install, the hardware clock will always be wrong. Check /etc/adjtime ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Centos 6 - What are you looking forward to?
On Mar 4, 2011, at 12:11 PM, John R Pierce wrote: IBM Power servers since the Power4+ CPU (they are up to Power7 now) have hardware partitioning support, commonly known as LPAR. LPAR can be divided in units of 1/10th of a CPU. The software to manage this is now called PowerVM (its been called other names in the past, not all polite). In addition, AIX 6.1 and newer have Workload Partitions (WPAR), which are similar to Solaris Zones, these allow subdividing an AIX install into an arbitrary number of apparently different systems that all share the same kernel. LPAR plus VIOS (Virtual IO System, actually a stripped down preconfigured AIX system) corresponds to the Xen model, however the base hypervisor capability is built right into the CPU and IO hardware, VIOS just provides management and optional virtualized IO. You can assign IO adapters directly to partitions, whereupon the partitions (VMs) run even if VIOS is shut down. The newer Power6 and 7 servers have Ethernet adapters that provide each LPAR with its own hardware-virtualized ethernet adapter so you don't need a cage full of cards, or run all the networking through VIOS. Wow, thats awesome, thanks for the John. - aurf ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Centos 6 - What are you looking forward to?
John R Pierce wrote: On 03/04/11 11:59 AM, m.r...@5-cent.us wrote: I'm looking forward to the new cgroups and KVM. This will give it some capabilities similar to AIX virtual partitions which can divvy up CPUs at a fine resolution. Really? So IBM ported VM into native AIX? I missed that. IBM Power servers since the Power4+ CPU (they are up to Power7 now) have hardware partitioning support, commonly known as LPAR. LPAR can be divided in units of 1/10th of a CPU. The software to manage this is now called PowerVM (its been called other names in the past, not all polite). snip Neat! Thanks - around '06 I was working as a developer on a big AIX system, but never administered one. mark (who worked under VM on a mainframe, years back) ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Centos 6 - What are you looking forward to?
On Fri, Mar 4, 2011 at 3:11 PM, John R Pierce pie...@hogranch.com wrote: IBM Power servers since the Power4+ CPU (they are up to Power7 now) have hardware partitioning support, commonly known as LPAR. LPAR can be divided in units of 1/10th of a CPU. The software to manage this is now called PowerVM (its been called other names in the past, not all polite). [informative text snipped] Yes, it is some nice stuff... In particular, having the hardware partitioning capability plays nice with Oracle licensing. Under KVM or Xen we still have to license the entire system. This probably won't change with the newer kvm, but one can hope. On the Linux side I would like to see how KSM (kernel memory merge) stacks up against memory compression on the Power7 side. Not sure if this made it into RHEL6, but hope springs eternal... Storage management is always a big issue for me. AIX has some really great tools for managing disks. In Linux the LUN, block and fs layer are still relatively decoupled which gives an enormous amount of flexibility but certain types of changes require multiple commands on Linux. On the desktop side I've been running RHEL6 as my primary environment since release. Transition was easy. My old kickstart files needed tweaking, but so far it's been a breeze. ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
[CentOS] KVM Question
I'm curious exactly how KVM works. If i see things right it's virtualization that's still within a full base operating system load correct? How does KVM perform against VMware which uses a much smaller footprint? Is KVM really a hypervisor? I'm just trying figure out the basics of KVM..:) Thanks, William Warren ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Centos 6
On Friday, March 04, 2011 09:48:03 am Simon Matter wrote: I'm not sure that's true. You have to understand that at the same time everybody should have worked on EL6.0, both EL5.6 and EL4.9 came out and for very good reason those responsible for CentOS decided to build those first. Just remember, the folks doing SL have been a bit faster with 6.0, but they did IIRC not do the 5.6 nor the 4.9 yet (maybe they rebuilt some packages to still be secure, but I think they didn't finish the full distribution). So, I'm quite sure it's not as bad as you think. Personally, I'd rather have my fixes for an older release (such as my in- production CentOS 4.x and 5.x servers) than get the latest stuff for development and new deployment while leaving older, still-in-production systems vulnerable. I wonder, though, if this wasn't intentional? By releasing all three at once, RH gang has delayed anybody deploying EL6 with any of the free as in beer solutions for at least a few months, giving them a sales edge. We may see this more in the future, because even if it wasn't intentional this time, they have undoubtedly seen the effect it has caused and may want to repeat it. Not that I mind that all much, it's their dime and they can do what they want with it. And the end result is still everything I'm looking for: stable, secure, reliable, even if not punctual. I'm curious to see if this represents the start of a trend. -Ben -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean. ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Updating hardware clock from cron
Is there a package to do this? Normally the hardware clock is set during shutdown if one is running ntpd. But if a long-running server shuts down unexpectedly, this isn't done, and the hardware clock might be off by a lot when it comes back up. So setting it periodically from a cron job could be useful. What do others do? Adding a one liner to /etc/cron.daily that invokes /etc/rc.d/init.d/ntpd would do it but it seems heavyweight to restart ntpd. Alas, the script doesn't export just the sync_hwclock function. I add this to /etc/rc.local /usr/sbin/ntpdate us.pool.ntp.org Sets the clock on start up. Might run it by cron once a month or so too. ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] CentOS and Marvell SAS/SATA drivers
On 03/04/2011 09:00 AM, Les Mikesell wrote: On 3/3/11 6:52 PM, Chuck Munro wrote: I've been on a real roller coaster ride getting a large virtual host up and running. One troublesome thing I've discovered (the hard way) is that the drivers for Marvell SAS/SATA chips still have a few problems. After Googling around quite a bit, I see a significant number of others have had similar issues, especially evident in the Ubuntu forums but also for a few RHEL/CentOS users. I have found that under heavy load (in my case, simply doing the initial sync of large RAID-6 arrays) the current 0.8 driver can wander off into the weeds after a while, less so for the older 0.5 driver in CentOS-5. It would appear that some sort of bug has been introduced into the newer driver. I've had to replace the Marvell-based controllers with LSI, which seem rock solid. I'm rather disappointed that I've wasted good money on several Marvell-based controller cards (2 SAS/SATA and 2 SATA). I replaced separate SII and promise controllers with a single 8-port Marvell based card and thought it was a big improvement. No problems with centos5.x, mostly running RAID1 pairs, one of which is frequently hot-swapped and re-synced. I hope its not going to have problems when I upgrade. Since I have the luxury of time to evaluate options, I've just downloaded Scientific Linux 6 to see what happens with either the mvsas or sata-mv driver. This is my first experience with SL but I wanted native ext4 rather than the preview version in CentOS-Plus. Even if I stick with SL-6 as the KVM host, I'll continue using CentOS as guest machines. If the Marvell drivers don't pan out, it looks like I'll have to either spend money on a 3Ware|LSI|Promise controller or revert to CentOS-Plus 5.5 for ext4. SL-6 is installing as I write this. Chuck ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Updating hardware clock from cron
On 03/04/11 12:40 PM, Matt wrote: I add this to /etc/rc.local /usr/sbin/ntpdate us.pool.ntp.org Sets the clock on start up. Might run it by cron once a month or so too. thats just the wrong way to go about it. if your clock is running fast, your cronjob will set it backwards, which will cause some interesting anomalies in anything time based, could cause a cronjob to trigger twice, funny timestamps in emails, etc. just setup NTP and forget about it, and it will always work right, unless your system is really badly broken, whereupon, it would be better to fix it than to continue to hack around like this. ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Updating hardware clock from cron
John R Pierce wrote: On 03/04/11 12:40 PM, Matt wrote: I add this to /etc/rc.local /usr/sbin/ntpdate us.pool.ntp.org Sets the clock on start up. Might run it by cron once a month or so too. thats just the wrong way to go about it. if your clock is running fast, your cronjob will set it backwards, which will cause some interesting anomalies in anything time based, could cause a cronjob to trigger twice, funny timestamps in emails, etc. just setup NTP and forget about it, and it will always work right, unless your system is really badly broken, whereupon, it would be better to fix it than to continue to hack around like this. Yup. And if you look in your logs, if the system is gracefully shut down, it syncs the hardware clock with the system time. mark ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Updating hardware clock from cron
On Friday, March 04, 2011 03:54:21 pm John R Pierce wrote: just setup NTP and forget about it, and it will always work right, unless your system is really badly broken, whereupon, it would be better to fix it than to continue to hack around like this. For the sake of the archives, VMware guests should be set to sync from the host using the VMware tools functionality, and then the host should run NTP, even and especially on ESX. VMware timekeeping in the guest can be made worse by running NTP inside the guest. This is a well-known VMware issue, and is covered in depth on the VMware knowledgebase. ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Updating hardware clock from cron
On 3/4/2011 3:59 PM, Lamar Owen wrote: On Friday, March 04, 2011 03:54:21 pm John R Pierce wrote: just setup NTP and forget about it, and it will always work right, unless your system is really badly broken, whereupon, it would be better to fix it than to continue to hack around like this. For the sake of the archives, VMware guests should be set to sync from the host using the VMware tools functionality, and then the host should run NTP, even and especially on ESX. VMware timekeeping in the guest can be made worse by running NTP inside the guest. This is a well-known VMware issue, and is covered in depth on the VMware knowledgebase. If you happen to have a server that gains time instead of loses it, note that a quick set to a time in the past will trigger an automatic shutdown of dovecot by dovecot due to fears of logging issues. I have two such machines... the rest lose time. John Hinton ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Updating hardware clock from cron
Lamar Owen wrote: On Friday, March 04, 2011 03:54:21 pm John R Pierce wrote: just setup NTP and forget about it, and it will always work right, unless your system is really badly broken, whereupon, it would be better to fix it than to continue to hack around like this. For the sake of the archives, VMware guests should be set to sync from the host using the VMware tools functionality, and then the host should run NTP, even and especially on ESX. VMware timekeeping in the guest can be made worse by running NTP inside the guest. This is a well-known VMware issue, and is covered in depth on the VMware knowledgebase. Excuse me? The last time I was following this closely, and I think the last time I looked, about a year ago, they said the opposite, that the guest, if running Linux, should use ntp. Right: NTP Recommendations Note: In all cases use NTP instead of VMware Tools periodic time synchronization. Also, you may need to open the firewall (UDP 123) to allow NTP traffic. at http://kb.vmware.com/selfservice/microsites/search.do?language=en_UScmd=displayKCexternalId=1006427 mark ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Gnu Screen - terminal issues
On 3/4/2011 12:07 PM, Dr. Ed Morbius wrote: I think you're fundamentally failing to understand my operating mode. Local system == Linux === my administrative center. Remote hosts. May be a dozen. May be 20,000. Or some number between or beyond. After reading this again, I'm wondering if you thought I was advocating running NX sessions directly to some large number of remote hosts. I didn't mean that. I just park a desktop session in a convenient place that doesn't happen to be at my own desk but I can pretend like it is, and almost all of my remote work originates from this desktop, mostly in terminal windows. I do have a few other sessions for work in a remote lab, access to VM's and some experimental stuff, but those are special cases where it is handy to only connect as needed. -- Les Mikesell lesmikes...@gmail.com ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Updating hardware clock from cron
On 03/04/11 12:59 PM, Lamar Owen wrote: On Friday, March 04, 2011 03:54:21 pm John R Pierce wrote: just setup NTP and forget about it, and it will always work right, unless your system is really badly broken, whereupon, it would be better to fix it than to continue to hack around like this. For the sake of the archives, VMware guests should be set to sync from the host using the VMware tools functionality, and then the host should run NTP, even and especially on ESX. VMware timekeeping in the guest can be made worse by running NTP inside the guest. This is a well-known VMware issue, and is covered in depth on the VMware knowledgebase. yeah, definately, VM of any sort is a whole different beast, and no way NTP should be run in a virtualized environment. ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
