[H-GEN] ext2 or ext3

[Bruce Campbell]

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On Thu, 20 Jun 2002, Tony Nugent wrote:

> On Thu Jun 20 2002 at 11:06, Jason Henry Parker wrote:
>
> > > An additional (handy) thing that you can do with the better journalled
> > > filesystems is to have the ability of 'snapshots', or 'this is what the
> > > filesystem looked like at previous point in time and this is the contents
> > > of the files at that point in time'.  _Not_ an alternative to backups,
> >
> > Also incredibly useful when you're trying to back up a busy filesystem
> > while it's still active, *if* you have the storage to keep the changes
> > and/or snapshot around long enough for the backup to be successful and
> > keep the `real' filesystem useful for users, no?
>
> I had no idea that ext3 could be used to do that.  (Very cool).

I have no idea whether ext3 can do that.  FreeBSD5's ffs can do this, and
as Jason points out, using it in order to get backups from a known
singular point in time is a suggested option.
(http://www.nluug.nl/events/sane2002/papers/kirk.ps)

> Do all journalling filesystems have this feature?

No.  Note carefully the word 'better'.  This may or may not apply in the
case of ext3 ;)

--==--
Bruce.


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