[libvirt-users] Cloning a volume via storage XML

[Weller, Lennart]

Hello everyone,

After the Bug with libvirt was found and fixed by Michal I am now
looking for a way to actually do the task I intended to do. I cannot
find any information if it is possible to clone a base-volume a la vol-
clone for ceph rbd.

As I posted in my addendum to the first post here I thought something
like this volume xml would do the job:

<volume>
   <name>coreos00.disk</name>
   <capacity unit="bytes">9116319744</capacity>
   <target>
       <format type="raw"></format>
       <permissions>
           <mode>644</mode>
       </permissions>
   </target>
   <backingStore>
       <path>vmdisks/coreos_2023</path>
       <format type="raw"></format>
   </backingStore>
</volume>

But even with the fix applied this simply creates an empty volume of
the given size. Granted this has no information about the snapshot so I
was sceptical that this would be enough in the first place.

If the vol-clone is not an option right now via volume xml it's not
that wild as I could just patch the terraform-libvirt-provider to do
the task beforehand but I wanted to know if it there exists an option
for libvirt to do it automatically when provided with an xml. I can't
find any options in the storage xml documentation so my guess would be
no.

Kind regards,
Lennart Weller