Re: [Evms-devel] Snapshotting an ext3 volume

[Kevin C. <kc...@au...>]

On Friday 29 November 2002 12:17, Michel Bouissou wrote:
> Le Vendredi 29 Novembre 2002 19:15, Kevin Corry a =E9crit :
> > First thing: if you are creating snapshots of journalled filesystems,=
 you
> > need to make sure you have the VFS lock patch applied to your kernel.=
 It
> > is available in the "kernel" directory of the EVMS 1.2.0 package. Thi=
s
> > patch will tell the original volume's filesystem to flush its data ju=
st
> > before the snapshot is created. This should prevent the need for a
> > journal replay on the snapshot.
>
> Uh... I believe I didn't apply this patch and was ignoring its existenc=
e
> :-( Why isn't it part of the "main" patch set, if it is important ?

I guess we always kept it as a separate patch because there was the chanc=
e=20
that someone already had that patch applied to their kernel. The installa=
tion=20
instructions should mention the VFS lock patch and that it is necessary f=
or=20
snapshotting journalled filesystems:
http://evms.sourceforge.net/install.html#kernel_support

> Well, I will apply it. Meanwhile, should I expect problems with the
> snapshots I have already created and copied onto backup media (and for
> which the journals were replayed at mount time) ?

You shouldn't see any problems with them. And actually, if you always cre=
ate=20
the snapshots read-write and replay the journals, the VFS lock patch may =
not=20
even be necessary.

Kevin Corry