[linux-lvm] Re: [catch22] lvm vs reiserfs

[Ed Tomlinson <tomlins@cam.org>]

On Thursday 22 March 2001 16:06, Ed Tomlinson wrote:

Chris et all,

Looks like reiserfs snapshots are broken with beta6 and ac22.
I had to upgrade to beta6 because of other problems (vgextend 
caused vgscan to fail...).  Now the snapshots are dead again.  
Note the VFS patch is still applied...

oscar# lvcreate -L 1G -s -n snap /dev/lv/root /dev/hda3
lvcreate -- WARNING: the snapshot must be disabled if it gets full
lvcreate -- INFO: using default snapshot chunk size of 64 KB for "/dev/lv/snap"
lvcreate -- doing automatic backup of "lv"
lvcreate -- logical volume "/dev/lv/snap" successfully created
 
oscar# mount /dev/lv/snap /snap -treiserfs -oro
reiserfs: checking transaction log (device 3a:04) ...
clm-2076: device is readonly, unable to replay log
Replay Failure, unable to mount
reiserfs_read_super: unable to initialize journal space
mount: wrong fs type, bad option, bad superblock on /dev/lv/snap,
       or too many mounted file systems

Ideas?
Ed

> On Thursday 22 March 2001 15:10, Chris Mason wrote:
> > On Thursday, March 22, 2001 02:46:31 PM -0500 Ed Tomlinson
> >
> > <tomlins@cam.org> wrote:
> > > Hi,
> > >
> > > I decided to really try out some of the features built into 2.4.  Using
> > > a 2.4.2-ac20 kernel I my root on /dev/lv/root as a reiserfs filesystem.
> > >  So far so good.  Now I want to back it up.  So I created a snapshot
> > > with lvcreate -L 50 -s -n snap /dev/lv/root.  This works too.  Problem
> > > happens when I want to mount /dev/lv/snap to back it up logically.  At
> > > this point reiserfs wants to replay its journal....  Of course it
> > > cannot
> > > (snapshot=ro).
> > >
> > > How can this be resolved?  Is there a way to sync root just after the
> > > lvm data gets updated in /etc but before the snapshot starts?  How else
> > > might this be fixed (is it fixed already somewhere)?
> >
> > Go to ftp.sistina.com, and grab 0.9.1_beta6.  Apply
> > linux-2.4.2-VFS-lock.patch that is included in PATCHES directory after
> > untarring.  This provides the rest of the lockfs API I coded with the LVM
> > guys.
>
> I updated to ac21 with the above patch.  I am using the lvm utilities from:
>
> deb ftp://ftp.sistina.com/pub/LVM/0.9/binaries/debian unstable main
>
> Now I can mount the snapshot.  Thanks.
>
> One loose end, is the journal-1777 message below something to worry about?
>
> oscar# lvcreate -L 50 -s -n snap /dev/lv/root
> lvcreate -- rounding up size to physical extent boundary "52 MB"
> lvcreate -- WARNING: the snapshot must be disabled if it gets full
> lvcreate -- INFO: using default snapshot chunk size of 64 KB for
> "/dev/lv/snap" journal-1777: buffer 16 bad state !PREPARED !LOCKED !DIRTY
> !JDIRTY_WAIT lvcreate -- doing automatic backup of "lv"
> lvcreate -- logical volume "/dev/lv/snap" successfully created
>
> TIA,
> Ed Tomlinson