[linux-lvm] Re: can't mount ext3 snapshot => needs_recovery flag always set on mounted ext3 partitions

[Joe Thornber]

On Fri, Aug 09, 2002 at 02:44:24PM +0200, Antoine wrote:
> 
> > Would a writeable snapshot help ?  Since you would be able to change
> > the needs_recovery flag specifically on the snapshot.
> 
> How can I have a writable snapshot ? LVM snapshots are supposed to
> be read-only, aren't they ?

Try LVM2, it supports writeable snapshots.

> But indeed if the journal data has not been committed on the original
> volume when the snapshot is taken, then the snapshot may have false data
> in it as, due to its read-only nature, it is not able to catch up the
> uncommitted journal data... Am I missing something ?

The point of the VFS patch you mentioned in an earlier email was to
ensure that the journals are flushed correctly before the snapshot is
taken.

- Joe