We've got some SANs providing iSCSI LVM storage to Proxmox VMs and we're in the process of replacing them with new SANs (iSCSI LVM again). Is there any way to live migrate the storage for running VMs from the old SANs' iSCSI to the new SANs' iSCSI? I can't believe this is an uncommon feature request, but it appears to be unsupported by Proxmox 8.3 that we're running.
To test this, I made both the old and new SAN's iSCSI volumes (both identically sized LVMs) available in the storage list of a Proxmox 8.3 server and then attempted VM -> Hardware -> Had Disk (virtio0) -> Disk Action -> Move Storage -> Target Storage -> new SAN iSCSI volume (plus Disk Image: CH 00 ID 0 LUN 0), clicked on "Move disk" and then got this error:
TASK ERROR: storage migration failed: can't allocate space in iscsi storage
Interestingly, if you select Target Storage -> local (and pick qcow2 format) instead, the live storage migration from iSCSI to qcow2 *does* work (you obviously need enough local storage to house the qcow2 file). However, then trying to go from qcow2 to the new SAN iSCSI volume fails with that same TASK ERROR. Is there a technical reason that live storage migration to any LVM iSCSI destination doesn't work (I'm hoping it's just not been implemented rather than being technically impossible)? As it stands, there isn't a way for us to move a VM between two iSCSI-based SANs without shutting it down and copying it offline at the moment, which seems unsatisfactory especially if it's a large VM.
To test this, I made both the old and new SAN's iSCSI volumes (both identically sized LVMs) available in the storage list of a Proxmox 8.3 server and then attempted VM -> Hardware -> Had Disk (virtio0) -> Disk Action -> Move Storage -> Target Storage -> new SAN iSCSI volume (plus Disk Image: CH 00 ID 0 LUN 0), clicked on "Move disk" and then got this error:
TASK ERROR: storage migration failed: can't allocate space in iscsi storage
Interestingly, if you select Target Storage -> local (and pick qcow2 format) instead, the live storage migration from iSCSI to qcow2 *does* work (you obviously need enough local storage to house the qcow2 file). However, then trying to go from qcow2 to the new SAN iSCSI volume fails with that same TASK ERROR. Is there a technical reason that live storage migration to any LVM iSCSI destination doesn't work (I'm hoping it's just not been implemented rather than being technically impossible)? As it stands, there isn't a way for us to move a VM between two iSCSI-based SANs without shutting it down and copying it offline at the moment, which seems unsatisfactory especially if it's a large VM.
