PVE 8.2.4
VM migration with CD drive mounted does not allow booting after migration to another node, where is no ISO file.
PVE allows to migrate, but VM will not boot up due to lack of ISO.
Not sure if it's a bug or expected.
It is known that a VM will not start (not even for making a backup) when the selected ISO cannot be found.
For all Proxmox knows, the ISO might be essential for booting. I don't think there's an option to prevent this, currently.
Maybe store your ISO's on a centrally shared or replicated storage to prevent this?
PVE 8.2.4
VM migration with CD drive mounted does not allow booting after migration to another node, where is no ISO file.
PVE allows to migrate, but VM will not boot up due to lack of ISO.
Not sure if it's a bug or expected.
I had filed this report [1] some time ago regarding HA migrations, but it really applies to any migration and any storage situation. I believe you can guess what reply you would get if you filed yours as a bug (which you absolutely can).