I have installed two nodes of PVE 6.3 in VMware workstation and what I noticed "online migration" is available even when there is no shared storage. As far as I remember shared storage is required to do that. So how does it work here?
online/live migration with local disks is supported since quite a bit, but it's a rather recent addition on the GUI as well. the target VM is started with an NBD server, and the source VM mirrors its disks via NBD as part of the migration.