1:11 a.m.
Hello,
I have a problem when i tried to hotplug a disk to a VM. Here is the situation.
We use a VM (let's call this backupVM) which is responsible of doing our VM backup by
:
- Making a snapshot of the VM we want to backup
- Attach the snapshot disk
- Make the copy using DD
- Unplug the snapshot disk and then delete snapshot.
For some reason that i don't know, for certain VM, the backupVM cannot hot plug the
snapshot disk.
I'm using ovirt 4.2.4
Here is what is see in engine.log
2018-08-04 19:52:30,496-10 ERROR
[org.ovirt.engine.core.bll.storage.disk.AttachDiskToVmCommand] (default task-61)
[361eca85-ca85-4e23-b292-cd8303a1a86d] Command
'org.ovirt.engine.core.bll.storage.disk.AttachDiskToVmCommand' failed:
EngineException: org.ovirt.engine.core.vdsbroker.vdsbroker.VDSErrorException:
VDSGenericException: VDSErrorException: Failed to HotPlugDiskVDS, error = internal error:
unable to execute QEMU command 'device_add': Failed to get shared
"write" lock, code = 45 (Failed with error FailedToPlugDisk and code 45)
Here is the vdsm.log
2018-08-04 19:51:38,512-1000 INFO (jsonrpc/5) [virt.vm]
(vmId='78ef239f-3cb3-4eef-921f-f989724009ef') Hotplug disk xml: <?xml
version='1.0' encoding='utf-8'?>
<disk address="" device="disk" snapshot="no"
type="file">
<source
file="/var/lib/vdsm/transient/225ec856-d661-4374-bb7d-8ea7168fe5f2-b641bb09-325a-4932-a9af-32c907e4a381.D52Nkj"
/>
<target bus="virtio" dev="vdg" />
<serial>c312a0c3-8c58-472f-99ad-cfbabb42337d</serial>
<driver cache="writethrough" error_policy="stop"
io="threads" name="qemu" type="qcow2" />
</disk>
(vm:3859)
2018-08-04 19:51:38,672-1000 ERROR (jsonrpc/5) [virt.vm]
(vmId='78ef239f-3cb3-4eef-921f-f989724009ef') Hotplug failed (vm:3867)
Traceback (most recent call last):
File "/usr/lib/python2.7/site-packages/vdsm/virt/vm.py", line 3865, in
hotplugDisk
self._dom.attachDevice(driveXml)
File "/usr/lib/python2.7/site-packages/vdsm/virt/virdomain.py", line 98, in f
ret = attr(*args, **kwargs)
File "/usr/lib/python2.7/site-packages/vdsm/common/libvirtconnection.py", line
130, in wrapper
ret = f(*args, **kwargs)
File "/usr/lib/python2.7/site-packages/vdsm/common/function.py", line 92, in
wrapper
return func(inst, *args, **kwargs)
File "/usr/lib64/python2.7/site-packages/libvirt.py", line 570, in
attachDevice
if ret == -1: raise libvirtError ('virDomainAttachDevice() failed', dom=self)
libvirtError: internal error: unable to execute QEMU command 'device_add': Failed
to get shared "write" lock
here is libvirtd log in /var/log/messages
libvirtd: 2018-08-05 05:51:38.637+0000: 4967: error : qemuMonitorJSONCheckError:389 :
internal error: unable to execute QEMU command 'device_add': Failed to get shared
"write" lock
Do you guys have any idea of what going on ? How can i check this lock ?