2

Background

I have a QEMU/KVM virtual machine whose virtual disk is a qcow2 file. To create snapshots, I have been using

sudo virsh snapshot-create-as <vm_name> <snapshot_name>

and now I can display them using, for example, virsh snapshot-list --tree:

$ sudo virsh snapshot-list --tree my_vm
snapshot_001
  |
  +- snapshot_002
      |
      +- snapshot_003

I want to rename these snapshots (e.g. from snapshot_00X to my_snapshot_00X), but there is no virsh snapshot-rename command. Both of the possible workarounds I can think of seem to have serious pitfalls, and I would be glad to know if there is a better one.

Workaround 1

I could do, for each snapshot that I want to rename:

sudo snapshot-edit <vm_name> <snapshot_name> --rename

and then edit contents of the <name> element in the resulting XML.

However, man virsh seems to warn strongly against this (my emphasis):

Note that changing a snapshot name must be done with care, since the contents of some snapshots, such as internal snapshots within a single qcow2 file, are accessible only from the original name.

Because the snapshots, in my case are indeed internal snapshots within a single qcow2 file, it sounds as though using virsh snapshot-edit could render them inaccessible.

Workaround 2

I could, I suppose, use qemu-img to convert the internal snapshots into external snapshots plus a backing file, and then rename them, and then recombine them into internal snapshots of a single qcow2 file.

But this is non-trivial, and would also require manually editing the VM to restore my ability to use commands like virsh snapshot-revert (without which, the snapshots are effectively useless). I would be very surprised if there is not a better way.

Question

Compared to the workarounds given above, is there a better way to rename a series of QEMU/KVM internal qcow2 snapshots that have been created with virsh snapshot-create-as, without losing the ability to run them via virsh snapshot-revert?

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