Red Hat Bugzilla – Bug 1282796
[Cinder] ThawVDSCommand fails when taking live snapshot without a guest agent
Last modified: 2016-05-25 21:50:32 EDT
Created attachment 1095481 [details]
Description of problem:
Taking live snapshot of a Vm with Cinder volumes (ceph backend) fails on logs and UI, it looks like that operation fails due to failure to find a guestagent on the Vm.
2015-11-17 14:45:48,990 INFO [org.ovirt.engine.core.bll.storage.CreateCinderSnapshotCommand] (DefaultQuartzScheduler_Worker-1) [108f473e] Ending command 'org.ovirt.engine.co
2015-11-17 14:45:53,626 ERROR [org.ovirt.engine.core.vdsbroker.vdsbroker.ThawVDSCommand] (org.ovirt.thread.pool-7-thread-44) [42818ef1] Failed in 'ThawVDS' method
2015-11-17 14:45:53,631 ERROR [org.ovirt.engine.core.dal.dbbroker.auditloghandling.AuditLogDirector] (org.ovirt.thread.pool-7-thread-44) [42818ef1] Correlation ID: null, Call
Stack: null, Custom Event ID: -1, Message: VDSM fury66.tlv.redhat.com command failed: Guest agent is not responding: Guest agent not available for now
2015-11-17 14:45:53,631 INFO [org.ovirt.engine.core.vdsbroker.vdsbroker.ThawVDSCommand] (org.ovirt.thread.pool-7-thread-44) [42818ef1] Command 'org.ovirt.engine.core.vdsbrok
er.vdsbroker.ThawVDSCommand' return value 'StatusOnlyReturnForXmlRpc [status=StatusForXmlRpc [code=19, message=Guest agent is not responding: Guest agent not available for no
Version-Release number of selected component (if applicable):
Steps to Reproduce:
1.take live snapshot of a Vm with cinder storage
operation throws Exceptions on Logs and fails on UI
operation should throw log Warnings and display a warning on UI
You can't freeze or thaw without a guest agent. Perhaps it's worth having a warning audit log, but let's leave it to PM to decide.
(In reply to Allon Mureinik from comment #1)
> You can't freeze or thaw without a guest agent. Perhaps it's worth having a
> warning audit log, but let's leave it to PM to decide.
Indeed, this is by design. There should be an event log similar to: "Failed to thaw guest filesystems on VM... The filesystems might be unresponsive until the VM is restarted.". @Ori - can you please attach a screenshot of the events tab?
Created attachment 1095892 [details]
cinder - live snapshot without guest
Attached a screenshot with the expected events errors regarding freeze/thaw when invoking live snapshot on a VM without a guest agent. @Ori - did you get anything different?
@Derez - That's the error message alright, note that when using a non cinder storage images this error messages become ui warnings, so, in order to keep the behavior consistent, this should be taken care of.
(In reply to Ori Gofen from comment #5)
> @Derez - That's the error message alright, note that when using a non cinder
> storage images this error messages become ui warnings, so, in order to keep
> the behavior consistent, this should be taken care of.
I don't follow.. What do you mean by consistent? In images we don't use freeze/thaw.
@derez I meant that the errors being thrown should lower level to warning, because that is the general behavior
The level is higher since failure in thaw is usually more severe than freeze (failure in thaw means that the VM is still frozen and unresponsive).
@Yaniv/Allon - what do you think, should we lower the level to warning? See the attached screenshot for reference: https://bugzilla.redhat.com/attachment.cgi?id=1095892
The error level is currently misleading - this isn't an important failure - the thawing failed since the freezing didn't succeed.
Let's reduce it to a warning.
oVirt 3.6.2 RC1 has been released for testing, moving to ON_QA
The only thing that's changed here is the event: "Failed to thaw guest filesystems on VM ..." (from error to warning)?
Anything else? messages in engine.log?
(In reply to Natalie Gavrielov from comment #11)
> The only thing that's changed here is the event: "Failed to thaw guest
> filesystems on VM ..." (from error to warning)?
Indeed. That's was the only issue. See https://bugzilla.redhat.com/show_bug.cgi?id=1282796#c9
> Anything else? messages in engine.log?
Verified using: rhevm-3.6.2-0.1.el6.noarch