You wouldn’t want to write to the same file at the same time, but otherwise it works fine.

Migration should be as simple as importing the existing ZFS stuff into the Proxmox OS. Having backups of important data is critical though.

If I understand correctly, you can specify directories that live on the Proxmox Host, and they appear inside the VM, right?

Inside a Container, yep. VMs can’t do bind mounts, and would need to use NFS to share existing data from the host to inside the VM.

How does this compare to using virtual storage?

Like a VM virtual disk? Those are exclusive to each VM and can’t be shared, so if you want multiple VMs to access the same data then NFS would be needed.

But containers with bind mounts don’t have that limitation and multiple containers can access the same data (such as media).

Also, how can I replicate the ZFS pools to an external machine?

ZFS replication would do that.

Proxmox supports ZFS natively with management in the WebUI. So you could get rid of TrueNAS entirely and not need to deal with HBA pass-through or anything.

You also wouldn’t need NFS or have to deal with shares, as the data is available directly to Proxmox Containers via bind mounts.

Yeah I think you found it, my server had the same symptoms and a bad RAM stick was the cause.

I didn’t say that, I said almost! Generally disk IO is where VMs fall short on performance vs a container, but it’s usually a pretty small difference.

Extra security and full isolation with its own kernel, so you can load kernel modules and such.

Also can run Windows in a VM when needed, or MacOS.

VMs are basically just as fast as containers, and the RAM overhead from a lightweight Linux VM is very small.