On the host (a laptop) I don’t have (explicitly configured) multipath configuration and multipath-tools is not installed. I have tried to define a new storage pool based on ZFS on a loopback device, but the behavior is the same.
I have tried to reproduce the behaviour in yet another LXD host, and there I wasn’t able to reproduce it. If you are not able to reproduce it in your systems, I guess this is related in some way to my hosts.
I am not able to reproduce it with the versions you mentioned.
But still it would be interesting to know what is causing this behavior.
IMHO just adding disks from the ZFS backed storage pool to the VM should not cause any multipath related setup to appear inside the guest.
Thanks a lot @jpelizaeus for your support.
At this point I’m short of ideas for troubleshooting. The issue happens on my professional laptop and on a production server with different versions of LXD.
If I find something new I’ll post it here.