Re: [CentOS-virt] Resizing EXT3 partition in guest instance CentOS5
Hi, I have an issue. I have already resize the partition using Gparted. Now how can i resize the actual image size in virtual manager? I do not see any option for me to change the size of the allocated hard disk. Please advise. Thanks! On Wed, Jan 26, 2011 at 6:54 PM, Poh Yong Hwang yong...@gmail.com wrote: Hi, Great! Thanks for the quick response. I will try it out then. Yes. I do have backup for the host as well as the guest nodes. :) Regards yongsan On Wed, Jan 26, 2011 at 6:43 PM, Lorenzo Quatrini lorenzo.quatr...@gmail.com wrote: Poh Yong Hwang ha scritto: Hi, I have two guest vm instance running CentOS 5 with ext3 partition. I will like to reduce 1 VM harddisk space and using the 'release' harddisk space to add onto my second VM. Basically I need to know how can I reduce and increase an ext3 partition in CentOS KVM. I did a search and basically i can do it by booting the VM using Knoppix and use Gparted to reduce and increase the diskspace. I am thinking of the following 1) Boot first VM using Knoppix 2) Reduce the ext3 partition disk size using Gparted 3) Shutdown the VM and resize the diskspace using Virtual Manager 4) Increae the diskspace of the second VM using Virtual Manager 5) Boot up second VM using Knoppix 6) Increase the ext3 partition disk size using Gparted 7) Reboot the second VM As this is the first time i am doing it, will these work? Anyone has experience resiziing their EXT3 partition in KVM environment before? Thanks! Regards yongsan I guess it would work, but just in case remember: do backup beforehand :D Regards Lorenzo ___ CentOS-virt mailing list CentOS-virt@centos.org http://lists.centos.org/mailman/listinfo/centos-virt ___ CentOS-virt mailing list CentOS-virt@centos.org http://lists.centos.org/mailman/listinfo/centos-virt
Re: [CentOS-virt] Resizing EXT3 partition in guest instance CentOS5
2011/2/6 Poh Yong Hwang yong...@gmail.com: Hi, I have an issue. I have already resize the partition using Gparted. Now how can i resize the actual image size in virtual manager? I do not see any option for me to change the size of the allocated hard disk. You're probably looking for the resize feature of the qemu-img command, I'm fairly sure that virt-manager doesn't do resizing: man qemu-img Best regards Kenni ___ CentOS-virt mailing list CentOS-virt@centos.org http://lists.centos.org/mailman/listinfo/centos-virt
Re: [CentOS-virt] Resizing EXT3 partition in guest instance CentOS5
Well, I can tell you how I do it. Might help. 1) create a new storage volume of the size you want with Virtual Manager. (Host detailsStorage tab) 2) shut down the VM and add the new volume to the VM ( it now has two virtual drives - the original and the new) 3) boot with clonezilla, clone one drive to the other. Then boot gparted and resize as needed 4) delete both drives from the vm, and then add back the new volume. Boot. 5) keep the old, smaller volume around for a while as backup. When you add a volume, Virtual Manager assigns a device name to it: hda to the first drive, hdb to the second, ect. So, you have to delete them both to get Virtual Manager to assign hda to the new one, otherwise the OS will not be able to boot. ___ CentOS-virt mailing list CentOS-virt@centos.org http://lists.centos.org/mailman/listinfo/centos-virt
Re: [CentOS-virt] Resizing EXT3 partition in guest instance CentOS5
Hi, Thanks but my issue is i do not have enough diskspace to create another partition of the size that i needed. Is there a way for me to reduce the actual image size? Thanks! On Mon, Feb 7, 2011 at 3:09 AM, compdoc comp...@hotrodpc.com wrote: Well, I can tell you how I do it. Might help… 1) create a new storage volume of the size you want with Virtual Manager. (Host detailsStorage tab) 2) shut down the VM and add the new volume to the VM ( it now has two virtual drives - the original and the new) 3) boot with clonezilla, clone one drive to the other. Then boot gparted and resize as needed 4) delete both drives from the vm, and then add back the new volume. Boot. 5) keep the old, smaller volume around for a while as backup. When you add a volume, Virtual Manager assigns a device name to it: hda to the first drive, hdb to the second, ect. So, you have to delete them both to get Virtual Manager to assign hda to the new one, otherwise the OS will not be able to boot. ___ CentOS-virt mailing list CentOS-virt@centos.org http://lists.centos.org/mailman/listinfo/centos-virt ___ CentOS-virt mailing list CentOS-virt@centos.org http://lists.centos.org/mailman/listinfo/centos-virt
Re: [CentOS-virt] Resizing EXT3 partition in guest instance CentOS5
Hi Kenni, Sorry i might have miss it but if i do a man of qemu-img, i do not see resize option. I only see create, convert, commit and info. Thanks On Mon, Feb 7, 2011 at 3:18 AM, Kenni Lund ke...@kelu.dk wrote: 2011/2/6 Poh Yong Hwang yong...@gmail.com: Hi, Thanks but my issue is i do not have enough diskspace to create another partition of the size that i needed. Is there a way for me to reduce the actual image size? Yes, like I wrote 10 minutes ago: qemu-img resize Best regards Kenni ___ CentOS-virt mailing list CentOS-virt@centos.org http://lists.centos.org/mailman/listinfo/centos-virt ___ CentOS-virt mailing list CentOS-virt@centos.org http://lists.centos.org/mailman/listinfo/centos-virt
Re: [CentOS-virt] Resizing EXT3 partition in guest instance CentOS5
2011/2/6 Poh Yong Hwang yong...@gmail.com: Hi Kenni, Sorry i might have miss it but if i do a man of qemu-img, i do not see resize option. I only see create, convert, commit and info. Ohh, I'm sorry then :( Guess the qemu-img version in CentOS 5 just is too old... qemu-img *is* the tool you want, nevertheless...you might want to use another system with a newer version of qemu-img to do the resizing or manually compiling a newer version of qemu-kvm on your current system (to avoid conflicts with the installed qemu-kvm version). Otherwise you'll have to use another approach, like the one compdoc proposed. Best regards Kenni ___ CentOS-virt mailing list CentOS-virt@centos.org http://lists.centos.org/mailman/listinfo/centos-virt
Re: [CentOS-virt] Resizing EXT3 partition in guest instance CentOS5
You can't add a drive temporarily and have Virtual Manager create the new volume there? I would think even a USB stick would work... ___ CentOS-virt mailing list CentOS-virt@centos.org http://lists.centos.org/mailman/listinfo/centos-virt
Re: [CentOS-virt] Resizing EXT3 partition in guest instance CentOS5
I am coming into this discussion a little late, so apologies if I ask for any information previously provided. I can help you with this, but I'll need to know the domU's file system layout to do so. Can you send the output of the following commands? * fdisk -l * mount * df -h And if you're using LVM: * vgdisplay * lvdisplay ~ Tom (Sent from my mobile.) On Feb 6, 2011, at 12:25, Poh Yong Hwang yong...@gmail.com wrote: Hi Kenni, Sorry i might have miss it but if i do a man of qemu-img, i do not see resize option. I only see create, convert, commit and info. Thanks On Mon, Feb 7, 2011 at 3:18 AM, Kenni Lund ke...@kelu.dk wrote: 2011/2/6 Poh Yong Hwang yong...@gmail.com: Hi, Thanks but my issue is i do not have enough diskspace to create another partition of the size that i needed. Is there a way for me to reduce the actual image size? Yes, like I wrote 10 minutes ago: qemu-img resize Best regards Kenni ___ CentOS-virt mailing list CentOS-virt@centos.org http://lists.centos.org/mailman/listinfo/centos-virt ___ CentOS-virt mailing list CentOS-virt@centos.org http://lists.centos.org/mailman/listinfo/centos-virt ___ CentOS-virt mailing list CentOS-virt@centos.org http://lists.centos.org/mailman/listinfo/centos-virt
Re: [CentOS-virt] Resizing EXT3 partition in guest instance CentOS5
2011/2/6 Thomas Smith theitsm...@gmail.com: I am coming into this discussion a little late, so apologies if I ask for any information previously provided. I can help you with this, but I'll need to know the domU's file system layout to do so. Can you send the output of the following commands? * fdisk -l * mount * df -h And if you're using LVM: * vgdisplay * lvdisplay KVM not Xen according to original post - and the partition in the guest has already been resized with gparted, so no reason to perform any more actions within the guest - only thing missing is to resize the qemu image on the host (I assume the OP is using regular file-based images in virt-manager as nothing has been mentioned about this, eg. not iSCSI, NFS, LVM, etc.). Best regards Kenni ___ CentOS-virt mailing list CentOS-virt@centos.org http://lists.centos.org/mailman/listinfo/centos-virt
Re: [CentOS-virt] Resizing EXT3 partition in guest instance CentOS5
Hi, Apologies for the late reply. Here is the result of the command: qemu-img info staging.img image: staging.img file format: raw virtual size: 195G (20971520 bytes) disk size: 196G Yes. I am looking to reduce this size to 100G. Thanks! On Mon, Feb 7, 2011 at 7:35 AM, Thomas Smith theitsm...@gmail.com wrote: I see. So we are looking to decrease the size, not increase it. (I also assumed we were talking about a disk image.) OP, what are you using as the backing storage device? That is, are you using a disk image or a block device? If you are using a disk image, what format is the image? QCOW2? RAW? Something else? * Use qemu-img info disk.img to determine this. Execute this command on the host. If you are using a block device, knowledge of your file system structure (on the host) will be necessary. On Sun, Feb 6, 2011 at 1:14 PM, Kenni Lund ke...@kelu.dk wrote: 2011/2/6 Thomas Smith theitsm...@gmail.com: I am coming into this discussion a little late, so apologies if I ask for any information previously provided. I can help you with this, but I'll need to know the domU's file system layout to do so. Can you send the output of the following commands? * fdisk -l * mount * df -h And if you're using LVM: * vgdisplay * lvdisplay KVM not Xen according to original post - and the partition in the guest has already been resized with gparted, so no reason to perform any more actions within the guest - only thing missing is to resize the qemu image on the host (I assume the OP is using regular file-based images in virt-manager as nothing has been mentioned about this, eg. not iSCSI, NFS, LVM, etc.). Best regards Kenni ___ CentOS-virt mailing list CentOS-virt@centos.org http://lists.centos.org/mailman/listinfo/centos-virt -- Thomas Smith Cell: 602-882-2917 ___ CentOS-virt mailing list CentOS-virt@centos.org http://lists.centos.org/mailman/listinfo/centos-virt ___ CentOS-virt mailing list CentOS-virt@centos.org http://lists.centos.org/mailman/listinfo/centos-virt
Re: [CentOS] Fan speed control on Supermicro X8DAL board with CentOS
On 06/02/11 07:00, Chuck Munro wrote: Hello folks, I'm having a difficult time trying to figure out why the CPU cooling fans run at full speed on my Supermicro X8DAL-3 motherboard. There doesn't seem to be any variable speed (the fans are PWM compatible) ... they either idle at almost nothing, or suddenly burst into a high-pitched scream that gets my ears bleeding after a few seconds. Once they jump to warp-10, they remain there. The Super-I/O chip on this board is a Winbond W83627DHG which does the temperature and voltage monitoring. Is anyone aware of which driver or kernel module I need for that chip in order to get control of the fans? The Supermicro web site and the board's manual aren't any help. Fresh installs of CentOS-5.5 and RHEL-6 don't exert any control by default. Installing the lm_sensors package and probing with the 'sensors' command didn't help either. Slowly going deaf ... Chuck Hi Chuck, The correct kernel module for your chipset is w83627ehf.ko. I'm not sure the driver actually controls fan speed, I thought it was more for monitoring (fan speeds, temps, voltages) but I could be wrong. My current system (not a Supermicro) controls variable fan speed from options within the BIOS. I can enable/disable fan speed control and select either voltage or PWM based control. The stock w83627ehf driver in RHEL5.5 is oldish (they were updated in 5.5 I think but are still over a year old now). ELRepo.org have an updated driver available (kmod-w83627ehf) based on a backport from kernel-2.6.34. I've just checked upstream and a few more patches have been committed since kernel-2.6.34 and the current kernel-2.6.37 so I'll look at updating the elrepo driver with those latest patches. Hope that helps. ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
[CentOS] OpenSSH could be faster...then why don't they path it??
https://www.psc.edu/networking/projects/hpn-ssh/hpn-v-ssh-tput.jpg
SCP and the underlying SSH2 protocol implementation in OpenSSH is network
performance limited by statically defined internal flow control buffers. These
buffers often end up acting as a bottleneck for network throughput of SCP,
especially on long and high bandwith network links. Modifying the ssh code to
allow the buffers to be defined at run time eliminates this bottleneck. We have
created a patch that will remove the bottlenecks in OpenSSH and is fully
interoperable with other servers and clients. In addition HPN clients will be
able to download faster from non HPN servers, and HPN servers will be able to
receive uploads faster from non HPN clients. However, the host receiving the
data must have a properly tuned TCP/IP stack.
My question is: So Why Does the original OpenSSH has limited statically
defined internal flow control buffers?? It could be way faster, even 10x!!
With the HPN-SCP path it could be the descendant of FTP! Why aren't there any
OpenSCP packages? ('normal SCP+HPN-SCP path+no local user needed for
SCP'ing+chroot by default')
Any opinions?
Thank you!
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Re: [CentOS] OpenSSH could be faster...then why don't they path it??
On Sun, Feb 6, 2011 at 7:20 AM, kellyremo kellyr...@zoho.com wrote:
https://www.psc.edu/networking/projects/hpn-ssh/hpn-v-ssh-tput.jpg
SCP and the underlying SSH2 protocol implementation in OpenSSH is network
performance limited by statically defined internal flow control buffers.
These buffers often end up acting as a bottleneck for network throughput of
SCP, especially on long and high bandwith network links. Modifying the ssh
code to allow the buffers to be defined at run time eliminates this
bottleneck. We have created a patch that will remove the bottlenecks in
OpenSSH and is fully interoperable with other servers and clients. In
addition HPN clients will be able to download faster from non HPN servers,
and HPN servers will be able to receive uploads faster from non HPN clients.
However, the host receiving the data must have a properly tuned TCP/IP
stack.
My question is: So Why Does the original OpenSSH has limited statically
defined internal flow control buffers?? It could be way faster, even 10x!!
They are likely erring on the side of safety. Dynamic buffers could
introduce some vulnerabilities. You can generate race conditions in
different ways, and whenever there's a dynamic run-time setting this
increases the exposure surface.
BTW, at the end of the linked article:
ms with buffer_append_space in HPN-SSH. If you are experiencing
disconnects due to a failure in buffer_append_space please let us
know. We're currently tracking some problems with this and we're
trying to gather more information to help resolve it.
With the HPN-SCP path it could be the descendant of FTP! Why aren't there
any OpenSCP packages? ('normal SCP+HPN-SCP path+no local user needed for
SCP'ing+chroot by default')
Any opinions?
Thank you!
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Re: [CentOS] OpenSSH could be faster...then why don't they path it??
Kellyremo wrote on Sun, 06 Feb 2011 04:20:40 -0800: Any opinions? Yes. Please carry it to the appropriate forum. Thanks. Kai ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
[CentOS] if the file changes send email about diff
I have 2 script. Script A, Script B. Script A is regulary watching the dhcpacks [dhcp release is configured to 2mins] in the logs, for the past 2 minutes. it writes the MAC addresses to a file [/dev/shm/dhcpacks-in-last-2min.txt] every 2 minutes. Ok, this is working, active clients are in this file. Super! Script B: http://pastebin.com/raw.php?i=wvhwhPWu I'm trying to create a script, that watches the changes in /dev/shm/dhcpacks-in-last-2min.txt file [in every 1 sec]. Ok. But: my watcher script [the pastebined] is not working fine...sometime it works, sometime it send that someone XY logged out, but it's not true! nothing happened, and the problem is not in the Script A. Can someone help me point out, what am i missing? How can i watch a file [in every sec], that contains only MAC addresses, and if someone doesn't get dhcpack in 2 minutes, the file /dev/shm/dhcpacks-in-last-2min.txt changes, and that clients MAC address will be gone from it, and i need to know, who was it [pastebined my script..but somethings wrong with it]. Thank you for any help..i've been pathing my script for days now.. :\ ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] if the file changes send email about diff
I'm trying to create a script, that watches the changes in /dev/shm/dhcpacks-in-last-2min.txt file [in every 1 sec]. Have look at Gamin, its designed for this type of thing... ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Fan speed control on Supermicro X8DAL board with CentOS
On Sun, 06 Feb 2011 12:09:12 + Ned Slider wrote: On 06/02/11 07:00, Chuck Munro wrote: Hello folks, I'm having a difficult time trying to figure out why the CPU cooling fans run at full speed on my Supermicro X8DAL-3 motherboard. There doesn't seem to be any variable speed (the fans are PWM compatible) ... they either idle at almost nothing, or suddenly burst into a high-pitched scream that gets my ears bleeding after a few seconds. Once they jump to warp-10, they remain there. The Super-I/O chip on this board is a Winbond W83627DHG which does the temperature and voltage monitoring. Is anyone aware of which driver or kernel module I need for that chip in order to get control of the fans? The Supermicro web site and the board's manual aren't any help. Fresh installs of CentOS-5.5 and RHEL-6 don't exert any control by default. Installing the lm_sensors package and probing with the 'sensors' command didn't help either. Slowly going deaf ... Chuck Hi Chuck, The correct kernel module for your chipset is w83627ehf.ko. I'm not sure the driver actually controls fan speed, I thought it was more for monitoring (fan speeds, temps, voltages) but I could be wrong. My current system (not a Supermicro) controls variable fan speed from options within the BIOS. I can enable/disable fan speed control and select either voltage or PWM based control. The stock w83627ehf driver in RHEL5.5 is oldish (they were updated in 5.5 I think but are still over a year old now). ELRepo.org have an updated driver available (kmod-w83627ehf) based on a backport from kernel-2.6.34. I've just checked upstream and a few more patches have been committed since kernel-2.6.34 and the current kernel-2.6.37 so I'll look at updating the elrepo driver with those latest patches. Hope that helps. Thanks Ned! I did go through the board's BIOS menus several times and could find only one fan control option, which ranges from always-fast for maximum performance to almost-silent for workstation use. No matter what the setting, the fans may start out slow but eventually jump to high speed. Updating the BIOS to the latest version made no difference. I also noticed that at all times the BIOS reports the CPU temperatures as Low no matter what the fan speed. The coolers are always cold to the touch. I sure hope I don't have a defective board ... it's a royal pain to have to remove one from a large server. I booted Ubuntu but the live-CD version doesn't have a working 'fancontrol' utility. I'd be tempted to install Ubuntu Server but I much prefer staying with CentOS and KVM to match all of the guest virtual machines it'll be running. Time to go through the mobo manual with a fine-tooth comb. :-) Chuck ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] if the file changes send email about diff
Gamin? can you give a link? Google doesn't bring up relevant links regarding it :O On Sun, 06 Feb 2011 06:33:00 -0800 Joseph L. Casale lt;jcas...@activenetwerx.comgt; wrote gt;I'm trying to create a script, that watches the changes in gt; /dev/shm/dhcpacks-in-last-2min.txt file [in every 1 sec]. Have look at Gamin, its designed for this type of thing... ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] if the file changes send email about diff
kellyremo wrote: Gamin? can you give a link? Google doesn't bring up relevant links regarding it :O http://www.google.com/linux?hl=enq=gaminbtnG=Search Note bene ^ ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] if the file changes send email about diff
On Sun, Feb 6, 2011 at 2:38 PM, Michael Klinosky m...@enter.net wrote: kellyremo wrote: Gamin? can you give a link? Google doesn't bring up relevant links regarding it :O yum search gamin will surely help. -- Eduardo Grosclaude Universidad Nacional del Comahue Neuquen, Argentina ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Fan speed control on Supermicro X8DAL board with CentOS
On 06/02/11 17:15, Chuck Munro wrote: On Sun, 06 Feb 2011 12:09:12 + Ned Slider wrote: On 06/02/11 07:00, Chuck Munro wrote: Hello folks, I'm having a difficult time trying to figure out why the CPU cooling fans run at full speed on my Supermicro X8DAL-3 motherboard. There doesn't seem to be any variable speed (the fans are PWM compatible) ... they either idle at almost nothing, or suddenly burst into a high-pitched scream that gets my ears bleeding after a few seconds. Once they jump to warp-10, they remain there. The Super-I/O chip on this board is a Winbond W83627DHG which does the temperature and voltage monitoring. Is anyone aware of which driver or kernel module I need for that chip in order to get control of the fans? The Supermicro web site and the board's manual aren't any help. Fresh installs of CentOS-5.5 and RHEL-6 don't exert any control by default. Installing the lm_sensors package and probing with the 'sensors' command didn't help either. Slowly going deaf ... Chuck Hi Chuck, The correct kernel module for your chipset is w83627ehf.ko. I'm not sure the driver actually controls fan speed, I thought it was more for monitoring (fan speeds, temps, voltages) but I could be wrong. My current system (not a Supermicro) controls variable fan speed from options within the BIOS. I can enable/disable fan speed control and select either voltage or PWM based control. The stock w83627ehf driver in RHEL5.5 is oldish (they were updated in 5.5 I think but are still over a year old now). ELRepo.org have an updated driver available (kmod-w83627ehf) based on a backport from kernel-2.6.34. I've just checked upstream and a few more patches have been committed since kernel-2.6.34 and the current kernel-2.6.37 so I'll look at updating the elrepo driver with those latest patches. Hope that helps. Thanks Ned! I did go through the board's BIOS menus several times and could find only one fan control option, which ranges from always-fast for maximum performance to almost-silent for workstation use. No matter what the setting, the fans may start out slow but eventually jump to high speed. Updating the BIOS to the latest version made no difference. I also noticed that at all times the BIOS reports the CPU temperatures as Low no matter what the fan speed. The coolers are always cold to the touch. I sure hope I don't have a defective board ... it's a royal pain to have to remove one from a large server. I booted Ubuntu but the live-CD version doesn't have a working 'fancontrol' utility. I'd be tempted to install Ubuntu Server but I much prefer staying with CentOS and KVM to match all of the guest virtual machines it'll be running. Time to go through the mobo manual with a fine-tooth comb. :-) Chuck You're welcome Chuck. Your question prompted me to update the elrepo kmod-w83627ehf driver package to the latest upstream source (kernel-2.6.37): http://lists.elrepo.org/pipermail/elrepo/2011-February/000488.html By all means give that package a try, but I'm not convinced it will address your problem in this case. Either way, it should be relatively quick and painless to test - updated packages should be available shortly. Maybe someone with more experience of this particular Supermicro M/B will pop up on the list :-) Regards, Ned ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] future version of bind for el5
2011/2/5 fakessh @ fake...@fakessh.eu: hello all the people I'd call http://people.redhat.com/ atkac ~ / official member of the team redhat for news of future versions of bind 9.7 for el5 sincerely RHEL 5.6 contains version 9.7 of bind. As soon as CentOS 5.6 is released, those packages will be available. ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] if the file changes send email about diff
On 7/02/2011, at 2:33 AM, kellyremo wrote: I have 2 script. Script A, Script B. Script A is regulary watching the dhcpacks [dhcp release is configured to 2mins] in the logs, for the past 2 minutes. it writes the MAC addresses to a file [/dev/shm/dhcpacks-in-last-2min.txt] every 2 minutes. Ok, this is working, active clients are in this file. Super! The past 2 minutes is not a good indication of active client (unless that's your maximum lease time). It would be better to look in the dhcp.leases file somewhere under /var. There are at least Perl libraries (and very likely Python libraries too) for parsing this file easily. Script B: http://pastebin.com/raw.php?i=wvhwhPWu I'm trying to create a script, that watches the changes in /dev/shm/dhcpacks-in-last-2min.txt file [in every 1 sec]. Why on earth are you putting it under /dev/shm/? Surely /tmp, /var/tmp, or /var/lib/FOO would be better. Ok. But: my watcher script [the pastebined] is not working fine...sometime it works, sometime it send that someone XY logged out, but it's not true! nothing happened, and the problem is not in the Script A. I think your log-out detection is faulty. The only way you could reasonably infer this is if either a DHCP RELEASE message has been received, or the lease has not been renewed after the lease-expiry. What is your lease-time? Can someone help me point out, what am i missing? How can i watch a file [in every sec], that contains only MAC addresses, and if someone doesn't get dhcpack in 2 minutes, the file /dev/shm/dhcpacks-in-last-2min.txt changes, and that clients MAC address will be gone from it, and i need to know, who was it [pastebined my script..but somethings wrong with it]. I would suggest a solution based around dhcp.leases and something like gamin Hope it helps, Cameron ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
[CentOS] RHEL/Centos6 handling disks w/4k sectors?
Does anyone know if 4k sectors will be handled better by the kernel in Centos6? I'd like to copy backups to a 750Gb laptop type drive for offsite storage but the best write speed I can get is about 8MB/sec even with dd to the raw disk which shouldn't have an issue with partition alignment. -- Les Mikesell lesmikes...@gmail.com ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] RHEL/Centos6 handling disks w/4k sectors?
On 02/06/11 1:14 PM, Les Mikesell wrote: Does anyone know if 4k sectors will be handled better by the kernel in Centos6? I'd like to copy backups to a 750Gb laptop type drive for offsite storage but the best write speed I can get is about 8MB/sec even with dd to the raw disk which shouldn't have an issue with partition alignment. what are you using on dd as the blocksize (bs=) ? should be a fairly large multiple of 4K, like 1048576 (eg, 1MB writes). I get 50-80MB/sec writes to a laptop drive hooked up to my windows desktop when I'm cloning said laptop drives. if you're only seeing 8MB, something is very wrong. ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
[CentOS] system clock
I am running CntOS 5 with Gnome. Every now and then I have noticed that the computer will somehow get the time wrong by several hours. Is there a simple way to adjust the time? So far the only way I have found is to boot into windows (it is a dual boot system), make the change there, and then get back into CentOS. Older versions of Red Hat and Fedora let you do it by right-clicking on the time display, if I recall correctly, but setting the time isn't one of the options in CentOS. Thanks Buz Davis ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] system clock
On Sun, 6 Feb 2011, Buz Davis wrote: To: centos@centos.org From: Buz Davis buzda...@earthlink.net Subject: [CentOS] system clock I am running CntOS 5 with Gnome. Every now and then I have noticed that the computer will somehow get the time wrong by several hours. Is there a simple way to adjust the time? So far the only way I have found is to boot into windows (it is a dual boot system), make the change there, and then get back into CentOS. Older versions of Red Hat and Fedora let you do it by right-clicking on the time display, if I recall correctly, but setting the time isn't one of the options in CentOS. If you are connecting to the internet, you can use a program called ntpd: Name : ntp Arch : i386 Version: 4.2.2p1 Release: 9.el5.centos.2.1 Size : 2.4 M Repo : installed Summary: Synchronizes system time using the Network Time Protocol (NTP). URL: http://www.ntp.org License: distributable Description: The Network Time Protocol (NTP) is used to synchronize a : computer's time with another reference time source. The ntp : package contains utilities and daemons that will synchronize : your computer's time to Coordinated Universal Time (UTC) via : the NTP protocol and NTP servers. The ntp package includes : ntpdate (a program for retrieving the date and time from remote : machines via a network) and ntpd (a daemon which continuously : adjusts system time). : : Install the ntp package if you need tools for keeping your : system's time synchronized via the NTP protocol. HTH Keith Roberts - Websites: http://www.karsites.net http://www.php-debuggers.net http://www.raised-from-the-dead.org.uk All email addresses are challenge-response protected with TMDA [http://tmda.net] - ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] RHEL/Centos6 handling disks w/4k sectors?
the best write speed I can get is about 8MB/sec A while back I researched 4k sector drives since most new drives have them now. There is a problem with speed if you get the partition wrong. The answer seems to be to creating a partition with 1 meg of unpartitioned space preceding the first partition. This causes sector 2048 to be the first sector of the partition, and avoids the problem. Newer versions of gparted do this for you automatically when you use it to create a partition. ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] system clock
On 02/06/2011 01:35 PM, Buz Davis wrote: I am running CntOS 5 with Gnome. Every now and then I have noticed that the computer will somehow get the time wrong by several hours. Is there a simple way to adjust the time? So far the only way I have found is to boot into windows (it is a dual boot system), make the change there, and then get back into CentOS. [...] CentOS likes to store the hardware system clock in GMT time. Windows likes to store it in the local time zone. The multi-hour switch is an artifact of dual booting with this disparity in play. If either system updates the hardware clock while running, the other OS will get thrown off by several hours. The fastest way to 'resync' the clock is using the ntpdate utiltity. It is part of the 'ntp' package. As root run: 'yum install ntp'. You can then reset the clock in CentOS by running 'ntpdate' as root. -- Benjamin Franz ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] system clock
On 6 Feb 2011, at 21:40, Buz Davis buzda...@earthlink.net wrote: Is there a simple way to adjust the time? Easy way - use the 'date' command, see http://linux.die.net/man/1/date Ben ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] system clock
On Sun, 6 Feb 2011, Benjamin Donnachie wrote: To: CentOS mailing list centos@centos.org From: Benjamin Donnachie benja...@py-soft.co.uk Subject: Re: [CentOS] system clock On 6 Feb 2011, at 21:40, Buz Davis buzda...@earthlink.net wrote: Is there a simple way to adjust the time? Easy way - use the 'date' command, see http://linux.die.net/man/1/date Could do Ben. But the idea of ntp is that it does it for you automatically, without having to intervene yourself and set the time manually :) Kind Regards, Keith Roberts - Websites: http://www.karsites.net http://www.php-debuggers.net http://www.raised-from-the-dead.org.uk All email addresses are challenge-response protected with TMDA [http://tmda.net] - ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] system clock
On 6 February 2011 22:33, Keith Roberts ke...@karsites.net wrote: Could do Ben. But the idea of ntp is that it does it for you automatically, without having to intervene yourself and set the time manually :) Agreed but OP asked, Is there a simple way to adjust the time?. Ben ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
[CentOS] OT - simple CAD program to design electronic circuits with
Hi all. Is there an electronic circuit design CAD package available for Centos 5.5 please? Kind Regards, Keith Roberts - Websites: http://www.karsites.net http://www.php-debuggers.net http://www.raised-from-the-dead.org.uk All email addresses are challenge-response protected with TMDA [http://tmda.net] - ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] system clock
On Sun, Feb 06, 2011 at 10:56:11PM +, Benjamin Donnachie wrote: On 6 February 2011 22:33, Keith Roberts ke...@karsites.net wrote: Could do Ben. But the idea of ntp is that it does it for you automatically, without having to intervene yourself and set the time manually :) Agreed but OP asked, Is there a simple way to adjust the time?. Depending upon OP's needs, as they are going to be dual booting, as far as I can tell from the post, the simplest thing would be to set the CentOS install to use localtime. To do that, edit /etc/adjtime. You'll see it says UTC. Change that to LOCAL Reboot. (Might be a way to put it into effect without a reboot, but I don't know) Run ntpdate pool.ntp.org which will set the time. Now, when you boot between the two of them, Windows and Linux, the time will stay the same. The problem is that both systems set the hardware to clock time when shutting down. -- Scott Robbins PGP keyID EB3467D6 ( 1B48 077D 66F6 9DB0 FDC2 A409 FA54 EB34 67D6 ) gpg --keyserver pgp.mit.edu --recv-keys EB3467D6 Xander: Dinner is served. And my very own recipe. Willow: Ooh, you pushed the button on the microwave that says 'popcorn'? Xander: Actually, I pushed 'defrost', but Joyce was there in the clinch. ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] OT - simple CAD program to design electronic circuits with
On 7/02/11 10:06 AM, Keith Roberts wrote: Is there an electronic circuit design CAD package available for Centos 5.5 please? I use Eagle CAD on my Mac and I know that there is a linux version. I'm pretty sure that we also use this on out student RHEL5 labs. They have a free version that is really pretty comprehensive. Cheers, -pete ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] system clock
On Sun, Feb 6, 2011 at 4:35 PM, Buz Davis buzda...@earthlink.net wrote: I am running CntOS 5 with Gnome. Every now and then I have noticed that the computer will somehow get the time wrong by several hours. Is there a simple way to adjust the time? So far the only way I have found is to boot into windows (it is a dual boot system), make the change there, and then get back into CentOS. Older versions of Red Hat and Fedora let you do it by right-clicking on the time display, if I recall correctly, but setting the time isn't one of the options in CentOS. To summarize what others have said: 1) The disparity is caused by using different clock settings from Linux to Windows. Deselect UTC to make it use local time. 2) Use ntpdate to sync the time. A few other points: 1) Linux maintains both a system and a hardware clock. On bootup, the system copies the hardware clock to the system time. There can be drift between the two clocks (especially in virtual environments), so on shutdown the system does a sync from the system to the hardware clock. 2) The ntpd daemon will not adjust the system time beyond a few minutes. If you want to hard set the time, you need to use ntpdate first then turn on ntpd to keep it accurate. ntpdate does allow the system to slowly adjust the clock and this is useful to keep logs sane. 3) Be careful when forcing a time change on a running system. Time shifting backwards can wreak havoc on certain applications such as databases. ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] OT - simple CAD program to design electronic circuits with
Keith Roberts wrote: Is there an electronic circuit design CAD package available for Centos 5.5 please? http://opencircuitdesign.com/xcircuit/ I haven't used it yet, so I don't really know what it's like. ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] [work] OT - simple CAD program to design electronic circuits with
Keith, One possibility is Kicad (start at http://kicad.sourceforge.net/wiki/index.php/Main_Page). I have been using this package recently and it has reached the stage of being very useful. At this time it lacks some of the features of commercial PCB CAD packages but the price is right and it is an active project so those features will probably come over time. Have fun, Paul On 06/02/2011 4:06 PM, Keith Roberts wrote: Hi all. Is there an electronic circuit design CAD package available for Centos 5.5 please? Kind Regards, Keith Roberts - Websites: http://www.karsites.net http://www.php-debuggers.net http://www.raised-from-the-dead.org.uk All email addresses are challenge-response protected with TMDA [http://tmda.net] - ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] OT - simple CAD program to design electronic circuits with
On 02/06/2011 05:57 PM, Michael Klinosky wrote: Keith Roberts wrote: Is there an electronic circuit design CAD package available for Centos 5.5 please? http://opencircuitdesign.com/xcircuit/ I haven't used it yet, so I don't really know what it's like. I've been using xcircuit for years, and found it to be fast, fairly easy to learn, and quite useful. Not so great if what you're trying to do is capture to perform SPICE simulations, but a really great 2D drawing tool. There are additional parts libraries for it available online, and it's not hard to create your own, either. Output/working files are Postscript, so they're easily opened and converted in GIMP if needed. -- KevinO ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] RHEL/Centos6 handling disks w/4k sectors?
On Sun, Feb 6, 2011 at 4:50 PM, compdoc comp...@hotrodpc.com wrote: the best write speed I can get is about 8MB/sec A while back I researched 4k sector drives since most new drives have them now. There is a problem with speed if you get the partition wrong. The answer seems to be to creating a partition with 1 meg of unpartitioned space preceding the first partition. This causes sector 2048 to be the first sector of the partition, and avoids the problem. Newer versions of gparted do this for you automatically when you use it to create a partition. This turns out to also be a significant issue with RHEL/CentOS 5 and virtualized OS images, where the upstream repository has 4096 byte blocks, whether NetApp or some other architecture. NetApp images in VMWare get unhappy if you use the standard allocated 63 blocks for the BIOS and partition records. They're much, much happer if the begging of the first logical volume begins at block 65, but there's no graceful way to set this up in anaconda or most configuration tools. You have to pre-script it with parted. ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] RHEL/Centos6 handling disks w/4k sectors?
On Sun, Feb 06, 2011 at 02:50:34PM -0700, compdoc wrote: the best write speed I can get is about 8MB/sec A while back I researched 4k sector drives since most new drives have them now. There is a problem with speed if you get the partition wrong. The answer seems to be to creating a partition with 1 meg of unpartitioned space preceding the first partition. This causes sector 2048 to be the first sector of the partition, and avoids the problem. Newer versions of gparted do this for you automatically when you use it to create a partition. Just did a SL 6.0 install on a machine with two Hitachi 2TB drives with 4K sectors. parted warned me that the default values I'd chosen weren't optimal for the sector size and I adjusted manually. Note that I set these drives up post-install -- no idea if Anaconda would have done the right thing or not. Ray ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] system clock
On Sun, Feb 6, 2011 at 7:56 PM, Kwan Lowe kwan.l...@gmail.com wrote: On Sun, Feb 6, 2011 at 4:35 PM, Buz Davis buzda...@earthlink.net wrote: I am running CntOS 5 with Gnome. Every now and then I have noticed that the computer will somehow get the time wrong by several hours. Is there a simple way to adjust the time? So far the only way I have found is to boot into windows (it is a dual boot system), make the change there, and then get back into CentOS. Older versions of Red Hat and Fedora let you do it by right-clicking on the time display, if I recall correctly, but setting the time isn't one of the options in CentOS. To summarize what others have said: 1) The disparity is caused by using different clock settings from Linux to Windows. Deselect UTC to make it use local time. 2) Use ntpdate to sync the time. A few other points: 1) Linux maintains both a system and a hardware clock. On bootup, the system copies the hardware clock to the system time. There can be drift between the two clocks (especially in virtual environments), so on shutdown the system does a sync from the system to the hardware clock. 2) The ntpd daemon will not adjust the system time beyond a few minutes. If you want to hard set the time, you need to use ntpdate first then turn on ntpd to keep it accurate. ntpdate does allow the system to slowly adjust the clock and this is useful to keep logs sane. 3) Be careful when forcing a time change on a running system. Time shifting backwards can wreak havoc on certain applications such as databases. ntpdate is normally executed at boot tiime by the ntp init script. If you're on an unconnected wireless or modem at the time, this command will fall through to using the local hardware clock, which is listed as a fudge server in ntp.conf, just in case you can't reach the real NTP servers. ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] RHEL/Centos6 handling disks w/4k sectors?
On 2/6/11 3:30 PM, John R Pierce wrote: Does anyone know if 4k sectors will be handled better by the kernel in Centos6? I'd like to copy backups to a 750Gb laptop type drive for offsite storage but the best write speed I can get is about 8MB/sec even with dd to the raw disk which shouldn't have an issue with partition alignment. what are you using on dd as the blocksize (bs=) ? should be a fairly large multiple of 4K, like 1048576 (eg, 1MB writes). I get 50-80MB/sec writes to a laptop drive hooked up to my windows desktop when I'm cloning said laptop drives. if you're only seeing 8MB, something is very wrong. Not all laptop drives use 4k sectors - probably just 750Gb and up. I was using obs=4M. I thought there was more to it than alignment - and changes were made in more current kernels to help with the speed. -- Les Mikesell lesmikes...@gmail.com ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] OpenSSH could be faster...then why don't they path it??
On Sun, Feb 6, 2011 at 7:20 AM, kellyremo kellyr...@zoho.com wrote: My question is: So Why Does the original OpenSSH has limited statically defined internal flow control buffers?? It could be way faster, even 10x!! Any opinions? Thank you! I think this thread would be very welcome on the comp.securty.ssh newsgroup, also available as a Google group. It's been dull over there, and as an old-time poster there, I think it would be a welcome discussion. More generally and for CentOS, this software has an *old* core, and its stability is critical. There are a lot of recent computational capabilities that weren't envisioned when it was written, and Keep It Simple, Stupid remains critical to this and other system utilities that have to run as trusted, critical services without updating every few weeks as the last round of changes introduces new or rediscovers old bugs. Like bind and sendmail and ftp, it doesn't need new features that often, and the software *must be* compatible with older clients and servers. If you want leading edge features, hop over to Fedora to test and refine it, then encourage its backport to RHEL and CentOS. ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
[CentOS] SSH AllowUser WildCard
Is it possible to allow a user to login from an changing hostname like: username@*hoststringfixed.com -- Stephen Cox ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] SSH AllowUser WildCard
On 07/02/11 06:08, Stephen Cox wrote: Is it possible to allow a user to login from an changing hostname like: username@*hoststringfixed.com man sshd_config AllowUsers This keyword can be followed by a list of user name patterns, separated by spaces. If specified, login is allowed only for user names that match one of the patterns. `*' and `?' can be used as wildcards in the patterns. Only user names are valid; a numerical user ID is not recognized. By default, login is allowed for all users. If the pattern takes the form USER@HOST then USER and HOST are separately checked, restricting logins to particular users from particular hosts. So wild cards can be used although it doesn't specifically state they can be used with the HOST part. Try it and see, my guess is it will work. ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
