Re: revert to static snapshot on reboot

["Niels de Carpentier" <niels@decarpentier.com>]

> On Mon, Jan 09, 2012 at 04:21:31PM +0100, Niels de Carpentier wrote:
>> > The plan that occurs to me is to make a snapshot of the system in the
>> > state that I want to always boot.  Then, I would rewrite the init
>> > script in the initrd to (a) delete any old tmp copy of the snapshot;
>> > (b) copy the static snapshot to a tmp copy; (c) mount the tmp copy.
>> >
>> > That's a little harder than I was hoping to work -- is there an easier
>> > way to get this functionality?
>>
>> I would just create a filesystem with the static content, and on boot
>> do:
>>
>> mount fs
>> delete snapshots
>> create snapshot
>> unmount fs and mount snapshot.
>>
>> I'm not sure if you can snapshot a snapshot, otherwise you could start
>> with a snapshot as well. (Just be sure not to delete it)
>
>    Yes, you can make snapshots of snapshots. A btrfs snapshot is a
> first-class citizen -- there's no real distinction between the
> original subvolume and a snapshot of it.

Good! That makes the op's case real simple. No need to copy any data, just
snapshot and mount.

Niels