Rather than converting the cold vm disk, couldn't you boot up the vm, dump the disks to stream, and send the streams into another format?

Yes, this is Microsoft's "agent-based migration" option mentioned in the article.

Agent based requires an insane amount of privileged accounts and I would say fails for 10%+ of the VM population

Try doing that to 3,000 production VMs.

Probably better to get the vm into a ramfs or any other way to not be currently on it. Otherwise it'll likely be pretty corrupted

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