Re: implementing soft-updates

Andreas Dilger (adilger@clusterfs.com)
Wed, 10 Apr 2002 12:13:04 -0600


On Apr 10, 2002 11:28 +0200, Dominik Kubla wrote:
> try to implement the snapshot capability for ext2/ext3. Everyone of us
> who has to do live backups of production systems will thank you if you
> get that development started.

LVM can already do snapshots at the device level. It integrates with
ext3/XFS/reiserfs via sync_super_lockfs/unlockfs so that what is in
the snapshot is a consistent, clean filesystem.

There might need to be a little touchup with ext2 to support these
calls, but even in the current state you get a usable filesystem
snapshot, with the exception that the filesystem has not been marked
clean.

As for a filesystem-level ext2/ext3 snapshot, this has also already
been done (sf.net/projects/snapfs). The people who took over that
project have removed all of the released files and CVS, but you can
still get the CVS from the sourceforge CVS backups. I also have a
version here, but don't have any time to work on it.

Cheers, Andreas

--
Andreas Dilger
http://www-mddsp.enel.ucalgary.ca/People/adilger/
http://sourceforge.net/projects/ext2resize/

- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/