Disable virtlockd

[Peter Krempa]

On Mon, Jun 08, 2020 at 16:26:44 +0200, Felix Queißner wrote:
> Hello!

Hi,

> 
> Is it possible to disable the virtlockd daemon

Yes. via the 'lock_manager' option in /etc/libvirt/qemu.conf

>or VM file locking? I

If you mean the image locking provided by qemu, then no, libvirt doesn't
have provisions to disable it.

> start qemu with a -snapshot option which prevents and changes to the
> disk image anyways.

Note that starting from libvirt-5.10 and qemu-4.2 any VM hacking in
-snapshot via qemu:arg will break as '-snapshot' is not supported
together with -blockdev which is used to configure disks.

This is because libvirt never really supported -snapshot.

Said that I still plan to add support for <transient/> disks but I'm
currently busy with other features.

> Using <readonly /> is not supported for IDE disks.
> 
> Another option would be to not require locking on the NFS share, but i
> have no idea how.

You didn't really describe the problem though. Are you trying to share
the disk images between multiple VMs?

Either way, another option is to add qcow2 overlay images which will
capture the writes and discard them after the VM is turned off.