From: "Niels de Carpentier" <niels@decarpentier.com>
To: "Hugo Mills" <hugo@carfax.org.uk>,
btrfs@spiritvideo.com, linux-btrfs@vger.kernel.org
Subject: Re: revert to static snapshot on reboot
Date: Thu, 12 Jan 2012 23:01:09 +0100 [thread overview]
Message-ID: <caac4792c203d54bce7dca9a10903263.squirrel@webmail.decarpentier.com> (raw)
In-Reply-To: <20120112213813.GA21769@carfax.org.uk>
> 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
next prev parent reply other threads:[~2012-01-12 22:01 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-01-09 6:43 revert to static snapshot on reboot btrfs
2012-01-09 9:51 ` Hugo Mills
2012-01-09 15:21 ` Niels de Carpentier
2012-01-12 21:38 ` Hugo Mills
2012-01-12 22:01 ` Niels de Carpentier [this message]
2012-01-09 18:43 ` Kai Krakow
2012-01-11 3:42 ` Anand Jain
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