<div dir="ltr"><div>Hello, <br></div><div><br></div><div>As far as I can see cinder hasn't implemented this. However, I'm not sure about the status of this feature because the last update was on 2014[1]</div><div><br></div><div>I think it's important to mention that this would only affect the live snapshots (handled by Nova) but for any other scenario every cinder driver optimized the snapshot/backup creation in a different way.</div><div><br></div><div>This sounds like a good PTG discussion topic. You can add it to the planning etherpad here:<br><a href="https://etherpad.opendev.org/p/yoga-ptg-cinder-planning">https://etherpad.opendev.org/p/yoga-ptg-cinder-planning</a><br><br>There's also info about the dates and times we'll be meeting on that etherpad.</div><div><br></div><div>Cheers,</div><div>Sofia<br></div><div><br></div><div>[1] <a href="https://blueprints.launchpad.net/cinder/+spec/quiesced-snapshots-with-qemu-guest-agent" target="_blank">https://blueprints.launchpad.net/cinder/+spec/quiesced-snapshots-with-qemu-guest-agent</a></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Tue, Aug 31, 2021 at 11:52 AM Arthur Outhenin-Chalandre <<a href="mailto:arthur.outhenin-chalandre@cern.ch" target="_blank">arthur.outhenin-chalandre@cern.ch</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">Hello,<br>
<br>
We are trying to trigger an fsfreeze via a cinder backup or snapshot. We<br>
confirmed that the fsfreeze hooks are actually called with a nova<br>
snapshot with `/var/log/qga-fsfreeze-hook.log` in the VM, but we can't<br>
achieve the same thing with a cinder backup/snapshot attached to the<br>
same instance. We are using Wallaby, libvirt, RBD for cinder volumes and<br>
RBD as well for cinder-backup.<br>
<br>
According to this (old) spec [0], cinder should call the `quiesce()`<br>
method in nova during backup/snapshot. We looked in the cinder code and<br>
couldn't find any clear evidence that this method is actually called by<br>
cinder (but we may have missed something). We added some debug messages<br>
on quiesce/can_quiesce/require_quiesce/... in<br>
`nova/virt/libvirt/driver.py` and they are never called with a cinder<br>
backup/snapshot in our setup while they are (and succeed) if we do a<br>
nova snapshot.<br>
<br>
We are starting to suspect that something is missing in cinder, but it<br>
could very well be a problem with our setup as well... Does someone use<br>
this feature or know if it should be working/implemented?<br>
<br>
[0]:<br>
<a href="https://wiki.openstack.org/wiki/Cinder/QuiescedSnapshotWithQemuGuestAgent#Cinder" rel="noreferrer" target="_blank">https://wiki.openstack.org/wiki/Cinder/QuiescedSnapshotWithQemuGuestAgent#Cinder</a><br>
<br>
Cheers,<br>
<br>
-- <br>
Arthur Outhenin-Chalandre<br>
<br>
</blockquote></div><br clear="all"><br>-- <br><div dir="ltr"><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div>
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