Re: [CentOS] HP Proliant ML150 : how do I access disks ?
On Wed, 2010-02-17 at 15:20 +0100, Rainer Duffner wrote: On 02/17/2010 03:38 PM, Rainer Duffner wrote: Hello there, I don't know about ML's but with DL series CentOS don't have any problems at all and with seeing disks in particular. So I presume that Rainer is absolutely right. You have to build an array first. Check this link http://docs.hp.com/en/9320/acu.pdf BTW: does 5.4 work on the latest G6 hardware? It does on my DL360 and BL460's ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS-virt] Live migration and DRBD
On Mon, 2009-11-30 at 11:43 -0500, Tait Clarridge wrote: On Mon, 2009-11-30 at 13:53 -0200, Gilberto Nunes wrote: Hi folks I deploy a two Dell PowerEdge T300 to test Virtualization with kvm+drbd+heartbaet. The KVM drbd and heartbeat work properly. However, I have doubt!! When the primary node has down, the secondary node start the VM that has original running on primary node... So, this required a full stop of hole system... This is not we wish here... Is there something way to live migrate VM from primary node that was shutdown I have no idea how to make this stuff working... Thanks for any help Currently there is work being done on a project for Xen called Remus. I am not sure about KVM but Remus is still in development and although it has been merged into the xen-unstable repository, it isn't completely ready yet (although the developers are working very hard). Basically it performs the first part of a live migration and if connection is lost, it will jump the virtual machine over to the secondary host. http://nss.cs.ubc.ca/remus/ It appears that Red Hat is including high availability for KVM in their Red Hat Enterprise Virtualization Manager for Servers. Not sure if this is going to make it to CentOS, can someone confirm/deny? There are 3 different things being discussed in this thread so far : 1. Live Migration 2. Virtual Machine HA 3. Continuous Mirroring / Replication (1) First of all Live Migration is not a HA solution, if your primary machine dies , there is no way to initiate a Live Migration anymore, as Live migration requires the home node to be still active, it can be used to migrate workloads away during maintenance slots etc , or to spread load, but not for HA. (2) So what people typically configure with HeartBeat is indeed the restart of a virtual machine from the same shared storage device. (3) Remus and Kemari are new kids in town they are going for RealTime Mirroring and therefore will implement real Virtual Machine HA. Remus is headed for Xen inclusion, while Kemari has just announced that they are also starting to work on a KVM port , but their current version was only Xen targeted. http://virtualization.com/guest-posts/2009/11/15/remus-and-kemari-still-going-strong/ Hope that clarifies some stuff .. __ _ 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] XEN and RH 6
On Tue, 2009-11-10 at 16:26 +0200, Pasi Kärkkäinen wrote: Both Novell and Oracle having been deeply involved in Xen lately, both are developing and supporting their own products based on Xen. Given the fact that Unbreakable is a source rebuild from RHEL, and Oracle is putting a lot of effort behind Xen , they hosted the Xen summit before, after the aquisition of Virtual Iron where they clearly defined their roadmap was Xen based, (not even including potential Xen based platforms they might get when the Sun acquisition eventually falls trough) So it looks to me that they will have to build a Dom0 based distribution anyhow. The bigger question however will be if and how this work can come back upstream and potentially be used in CentOS ? What's the idea on that ? greetigns Kris ___ CentOS-virt mailing list CentOS-virt@centos.org http://lists.centos.org/mailman/listinfo/centos-virt
Re: [CentOS] [DRBD-user] Unexplained reboots in DRBD82 + OCFS2 setup
On Thu, 2009-06-25 at 11:42 +0200, Kris Buytaert wrote: Use a serial console, attach that to some monitoring host. (you can useUSB-to-Serial, they are cheap and work), and log on that one. You'll get the last messages from there. I indeed had hoped to see some output on on the serial console when the reboots happened .. but the best I got so far was a partial timestamp with no further explanation before the reboot output started again .. Any other ideas ? Update : The problem is indeed ocfs2 fencing off the systems , the logging however does not show up in a serial console it DOES show up when using netconsole [base-r...@ccmt-a ~]# nc -l -u -p (8,0):o2hb_write_timeout:166 ERROR: Heartbeat write timeout to device drbd0 after 478000 milliseconds (8,0):o2hb_stop_all_regions:1873 ERROR: stopping heartbeat on all active regions. ocfs2 is very sorry to be fencing this system by restarting , One'd think that it output over Serial console before it log over the network :) It doesn't . Next step is that I`ll start fiddling some more with the timeout values :) ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] [Ocfs2-users] Unexplained reboots in DRBD82 + OCFS2 setup
On Wed, 2009-06-24 at 12:02 -0700, Sunil Mushran wrote: Do you have a separate network path for drbd traffic? If you do not, then you are probably overloading the network. In this case, I believe drbd is unable to replicate the ios fast enough and thus is blocking the o2cb disk heartbeat. One workaround is to increase the O2CB_HEARTBEAT_THRESHOLD to more than the default of 60 secs. Refer to the ocfs2 faq or ocfs2 1.4 user's guide for more on this. I've already modified the O2CB_HEARTBEAT_TRESHOLD to different values (120, 240 etc), with no changes.. And if you want to capture the logs, setup netconsole. /dev/console is a serial device connected to a terminal server, so far the best I got was a partial timestamp before I saw the output of the reboot again .. It tries to log .. but doesn't finish writing it :( But mostly there is no activity at all on the serial console :( Any other ideas ? greetings Kris Kris Buytaert wrote: We're trying to setup a dual-primary DRBD environment, with a shared disk with either OCFS2 or GFS. The environment is a Centos 5.3 with DRBD82 (but also tried with DRBD83 from testing) . Setting up a single primary disk and running bonnie++ on it works. Setting up a dual-primary disk, only mounting it on one node (ext3) and running bonnie++ works When setting up ocfs2 on the /dev/drbd0 disk and mounting it on both nodes, basic functionality seems in place but usually less than 5-10 minutes after I start bonnie++ as a test on one of the nodes , both nodes power cycle with no errors in the logfiles, just a crash. When at the console at the time of crash it looks like a disk IO (you can type , but actions happen) block happens then a reboot, no panics, no oops , nothing. ( sysctl panic values set to timeouts etc ) Setting up a dual-primary disk , with ocfs2 only mounting it on one node and starting bonnie++ causes only that node to crash. On DRBD level I get the following error when that node dissapears drbd0: PingAck did not arrive in time. drbd0: peer( Primary - Unknown ) conn( Connected - NetworkFailure ) pdsk(UpToDate - DUnknown ) drbd0: asender terminated drbd0: Terminating asender thread That however is an expected error because of the reboot. At first I assumed OCFS2 to be the root of this problem ..so I moved forward and setup an ISCSI target on a 3rd node, and used that device with the same OCFS2 setup. There no crashes occured and bonnie++ flawlessly completed it test run. So my attention went back to the combination of DRBD and OCFS I tried both DRBD 8.2 drbd82-8.2.6-1.el5.centos kmod-drbd82-8.2.6-2 and the 83 variant from Centos Testing At first I was trying with the ocfs2 1.4.1-1.el5.i386.rpm verson but upgrading to 1.4.2-1.el5.i386.rpm didn't change the behaviour Anyone has an idea on this ? How can we get more debug info from OCFS2 , apart from heartbeat tracing which doesn't learn me nothing yet .. in order to potentially file a valuable bug report. ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
[CentOS] Unexplained reboots in DRBD82 + OCFS2 setup
We're trying to setup a dual-primary DRBD environment, with a shared disk with either OCFS2 or GFS. The environment is a Centos 5.3 with DRBD82 (but also tried with DRBD83 from testing) . Setting up a single primary disk and running bonnie++ on it works. Setting up a dual-primary disk, only mounting it on one node (ext3) and running bonnie++ works When setting up ocfs2 on the /dev/drbd0 disk and mounting it on both nodes, basic functionality seems in place but usually less than 5-10 minutes after I start bonnie++ as a test on one of the nodes , both nodes power cycle with no errors in the logfiles, just a crash. When at the console at the time of crash it looks like a disk IO (you can type , but actions happen) block happens then a reboot, no panics, no oops , nothing. ( sysctl panic values set to timeouts etc ) Setting up a dual-primary disk , with ocfs2 only mounting it on one node and starting bonnie++ causes only that node to crash. On DRBD level I get the following error when that node dissapears drbd0: PingAck did not arrive in time. drbd0: peer( Primary - Unknown ) conn( Connected - NetworkFailure ) pdsk(UpToDate - DUnknown ) drbd0: asender terminated drbd0: Terminating asender thread That however is an expected error because of the reboot. At first I assumed OCFS2 to be the root of this problem ..so I moved forward and setup an ISCSI target on a 3rd node, and used that device with the same OCFS2 setup. There no crashes occured and bonnie++ flawlessly completed it test run. So my attention went back to the combination of DRBD and OCFS I tried both DRBD 8.2 drbd82-8.2.6-1.el5.centos kmod-drbd82-8.2.6-2 and the 83 variant from Centos Testing At first I was trying with the ocfs2 1.4.1-1.el5.i386.rpm verson but upgrading to 1.4.2-1.el5.i386.rpm didn't change the behaviour Anyone has an idea on this ? How can we get more debug info from OCFS2 , apart from heartbeat tracing which doesn't learn me nothing yet .. in order to potentially file a valuable bug report. thnx in advance Kris ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
Re: [CentOS-virt] Web based management system for Xen
On Wed, 2008-05-14 at 21:59 +0200, Fabian Arrotin wrote: On Wed, 14 May 2008, Karanbir Singh wrote: Can anyone recommend a web based management panel that would let me bring up / tear down and do some basic management for a bunch of Xen VM's ? Special bonus points if the panel can manage remote Xen Hosts :D I've never used/tested it but it seems OpenQRM can manage Xen VM's (as well as deploying newer DomU's). There is a virtual appliance (built on CentOS ;-) ) that can be downloaded from the openqrm website : http://www.openqrm.org/openqrm-virtual-appliance.html But i can't speak of openqrm because i've no experience with it .. but i know that some experimented people (subscribed to this list) use it on a day-to-day basis, isn't it Kris ? ;-) Mailinglist need Name highlighting :) I`m not using openQRM on a day to day basis, but I have been implementing it to manage virtual machine deployment , migrations and management before. http://www.krisbuytaert.be/published_articles/openQRM-Xen/ (Note that this is for the 3.X series :) It also features live migration as documented here (I hope the link works as Youtube is blocked at the custumer I am with today) http://www.google.com/url?sa=tct=rescd=1url=http%3A%2F% 2Fwww.youtube.com%2Fwatch%3Fv% 3DEeqQC5SoPvsei=7f8rSKOrE5aKxAGXrpyYBgusg=AFQjCNGthXmkTTYJQjyvPIcVylu3WIIv3Qsig2=nepxE_sskKNc8_Dlav8LMg greetz Kris ___ CentOS-virt mailing list CentOS-virt@centos.org http://lists.centos.org/mailman/listinfo/centos-virt
