PDM - ? Live migration between two unclustered hosts w/ shared vms

[mpeters]

I am trying to live migrate a vm on shared storage between two unclustered hosts using PDM.

Both hosts are sharing the vm using the identical NFS share.

The migration works, but the process takes several minutes. In addition to moving the "virtual machine state" and config file to the other host, it copies the entire vm to the same share, then deletes the old copy.

Is there any way to just migrate the "virtual machine state" and config file without the overhead of redundantly copying the entire vm?

 

[fabian]

no, because the two nodes are not in a cluster, thus there is no knowledge about the storage being shared.

even worse, giving access to the same storage to two clusters (or standalone nodes) without any sort of separation/namespacing/.. is really really dangerous, since both PVE systems will assume they have full ownership of the storage, and can therefore delete volumes used by the other one (or cause other corruption, depending on the storage type).

 

[mpeters]

Ok, but as I understand it...

When you remove a storage entry in Proxmox, you are primarily removing the configuration that tells Proxmox how to connect to that storage. The actual virtual machine data (disks) will remain on the physical storage device itself, but the VMs will effectively be "lost" from the Proxmox interface and become unusable because Proxmox no longer knows where to find their disk images. And when you add the storage entry, the volumes reappear.

When a host attempts to create a new vmid on the share, the host should return an error if the vmid folder on the share already exists. And when migrating a vm between hosts, the corresponding vmid.conf file is transferred to the destination host along with the "virtual machine state", so the corresponding vmid.conf is removed from the source host.

Am I missing something?