Can you run 2 clones of a VM at the same time that includes a memory snapshot ?

[ayoubfaouzi]

Hello team,

Let's assume I suspended a VM. Then I made 2 clones of that VM (MacOS Tahoe).

Can I have them both running at the same time ? I know that the state include the mac adress, and apple virtualization framework don't like when you have a mismatch between the mac address in the VM config and the one in the snapshot. Any workaround for that ?

The goal is to have multiple VMs running based on a clone that includes a memory state so we can avoid the boot time overhead. Basically Restore a VM quickly, do some work and throw it out.

Another question that I was wondering about was: Why does tart delete the snapshots after it has been resumed ? Can't we make some changes to a VM then revert it state, and it should work just fine ? Any rationale behind that ?

[edigaryev]

Can I have them both running at the same time ?

Unfortunately it's not possible, because Virtualization framework expects the MAC address of a suspended VM to be the same when resuming it.

Another question that I was wondering about was: Why does tart delete the snapshots after it has been resumed ? Can't we make some changes to a VM then revert it state, and it should work just fine ? Any rationale behind that ?

Since the MAC address is only re-generated when a runtime collision is imminent, it's easy to achieve what you want by using tart clone:

1. Create a golden VM, start it with --suspendable, perform initial setup, suspend it
2. Clone a throwaway VM from the golden VM, start it with --suspendable, do things with it
3. Stop and delete the throwaway VM
4. Go to step number 2

As for the rationale, the only reason besides just historical precedent (#527) I can think of is that it's simpler than introducing an additional CLI command like tart reset, which will allow the user to remove a snapshot for a VM.

[ayoubfaouzi]

Thanks a lot for your return @edigaryev. That answers my question.