Bug 571557
| Summary: | RHEL 5: Managing vms with clustertools and libvirt | |||
|---|---|---|---|---|
| Product: | Red Hat Enterprise Linux 5 | Reporter: | Shane Bradley <sbradley> | |
| Component: | doc-Cluster_Administration | Assignee: | Steven J. Levine <slevine> | |
| Status: | CLOSED ERRATA | QA Contact: | ecs-bugs | |
| Severity: | medium | Docs Contact: | ||
| Priority: | medium | |||
| Version: | 5.4 | CC: | abaron, iannis, mhideo, slevine, syeghiay, tao, teigland | |
| Target Milestone: | rc | Keywords: | Documentation | |
| Target Release: | --- | |||
| Hardware: | All | |||
| OS: | Linux | |||
| Whiteboard: | ||||
| Fixed In Version: | Doc Type: | Bug Fix | ||
| Doc Text: | Story Points: | --- | ||
| Clone Of: | ||||
| : | 746776 772324 (view as bug list) | Environment: | ||
| Last Closed: | 2012-02-21 05:18:33 UTC | Type: | --- | |
| Regression: | --- | Mount Type: | --- | |
| Documentation: | --- | CRM: | ||
| Verified Versions: | Category: | --- | ||
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | ||
| Cloudforms Team: | --- | Target Upstream Version: | ||
| Embargoed: | ||||
| Bug Depends On: | ||||
| Bug Blocks: | 746776, 772324 | |||
| Deadline: | 2011-11-04 | |||
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Description
Shane Bradley
2010-03-08 20:29:52 UTC
While we layer on top of libvirt with the cluster tools, the converse is not true. We do not layer the libvirt tools on top of the cluster stack for any purpose; libvirt is not designed nor intended to be cluster-aware. One method to reduce the chances of "double-start" problems due to mistakes while using cluster/non-cluster tools in a clustered environment is to: * use rgmanager 2.0.52-1.el5_4.3 or later package release, and * store the virtual machine configuration files in a non-default location. This non-default location may reside anywhere. The advantage of using an NFS share or a shared GFS or GFS2 file system is that the administrator does not need to keep the configuration files in sync across the cluster members. However, it is also permissible to use a local directory as long as the administrator keeps the contents synchronized somehow cluster-wide. In the cluster configuration, virtual machines may reference this non-default location by using the "path" attribute. (Note: The 'path' attribute is a directory or set of directories separated by the colon ':' character, not a path to a specific file!) This makes it more difficult to accidentally "start" a VM using xm or virsh, as the config file will be unknown out of the box to libvirt or the xm tool. John -- I'm just looking at this for the first time, as part of a final RHEL 5.7 check -- it wasn't assigned to me so I had missed it. I'm not sure where this will go for RHEL 5 (where it goes in RHEL 6 is also uncertain, although it looks as if I can incorporate it into the new Managing Virtual Machines document that I'm working on, if it applies to that release as well). But I think there's no way we're going to address this for RHEL 5.7 this week. Can we move this to RHEL 5.8? I sent this note to Lon on 10/15, so I'm moving this to NEEDINFO: Lon, In response to BZ#571557, I am adding a small section to the RHEL 5 Cluster Administration document on configuring virtual machines in a cluster, with the information you provided in that bug. Could you look over what I've written? http://documentation-stage.bne.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/5/html/Cluster_Administration/s1-vm-considerations-CA.html I also added an "Important" note before Table C.21, the table of virtual machine resource parameters: http://documentation-stage.bne.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/5/html/Cluster_Administration/ap-ha-resource-params-CA.html#tb-vm-resource-CA After you review this, I'll write something similar up for RHEL 6 -- but I need to check on what virtual machine tools we support -- we don't support virsh in RHEL 6, do we? -Steven The first section looks great. Second section looks fine, but maybe we should indicate the corruption is specifically in the VMs themselves. Lon: The second section, the "Important" note, includes this sentence: "Using virsh or libvirt tools to start the machine can result in the virtual machine running in more than one place, which can cause data corruption." Would adding just a few word clarify this: "Using virsh or libvirt tools to start the machine can result in the virtual machine running in more than one place, which can cause data corruption in the virtual machine." That same sentence also appears in the first section, so I would add this in both places. -Steven Latest build: Red_Hat_Enterprise_Linux-Cluster_Administration-5-web-en-US-5-49.el6eng New sentence noted in Comment 21 is here: http://documentation-stage.bne.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/5/html/Cluster_Administration/s1-vm-considerations-CA.html And here: http://documentation-stage.bne.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/5/html/Cluster_Administration/ap-ha-resource-params-CA.html#tb-vm-resource-CA As an "Important" note preceding table C.21. Fixed and checked in, but I can't put this back into ON_QA until we can build on Brew. Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory, and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. http://rhn.redhat.com/errata/RHBA-2012-0175.html |