VM created via Cockpit Machines hangs randomly

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1

I have an Alma 9.3 VM host. I set up and run the VMs on the host though the Cockpit Machines interface. The host is using ZFS to pool some large drives. I am sharing one dataset from the ZFS pool as a shared directory with an Alma 9.3 VM, again through the Cockpit Machines interface.

The VM that is sharing the pool randomly hangs from time to time, I believe because the shared directory stops responding for a while. To speed up recovery of the VM, I added a watchdog to the VM that reboots the VM when the file system becomes unresponsive. I can see the VM now reboots about 2-5 times a day most days. I haven’t lost any data, but I’d like to get the VM stable.

I don’t see anything in the host or VM logs about why this might be happening. I replaced and expanded the RAM on the host in case it was a memory error.

Any ideas about how to troubleshoot this? I am at a loss.

2

Ok, in case anyone ever has the same problem, here is how I was able to fix it.

First, it seems there is a bug that causes virtiofs to hang. I suspect this is the source of my problem.

Instead of using virtiofs, I switched over to using NFS to share the directory. This post was quite useful in showing how to configure nfs to this end.