[linux-lvm] Snapshots of snapshots are not supported yet

[Zdenek Kabelac]

Dne 8.7.2013 18:05, markw at mohawksoft.com napsal(a):
> I'm trying to get a snapshot of a snapshot. I know the new thin
> provisioning stuff supports this, but I'm not sure the release state is
> something I can use at a customer.
>
> Using LVM2, the snapshot format is tried and true, but inefficient if you
> want to take multiple snapshots.
>
> Looking at dmsetup, there doesn't seem like there would be an issue taking
> a snapshot of a snapshot, but it is disabled in the tools.
>
> I guess my question is this: Can it be done? Is there any reason why it
> should not work?
>

1. Noone has written support for it in lvm2. And AFAICK noone is working on this.

2. Since the activation order of old snapshot is not as simple as with other 
targets, it's currently not so easy to add support for into lvm deptree
resolver.

Zdenek