[linux-lvm] LVM ext3 support

[linux-lvm] LVM ext3 support

[anthony mayes]

I am running Redhat 9 with kernel 2.4.20-20.9.  I am getting the 
following errors when trying to mount an LVM snapshot:

EXT3-fs: INFO: recovery required on readonly filesystem.
EXT3-fs: write access unavailable, cannot proceed.

I saw a thread on redhat.com that said a kernel patch is needed.  My 
question is where can I get the patch for this kernel, how do I install 
it, and why isn't this built into the kernel in the first place?  Any 
other suggestions are welcome.

Thanks in advance.

-- 
Anthony Mayes
UNIX Server Administration
Southern Illinois University Edwardsville
anmayes@siue.edu

[linux-lvm] Re: LVM ext3 support

[Måns Rullgård]

anthony mayes <anmayes@siue.edu> writes:

> I am running Redhat 9 with kernel 2.4.20-20.9.  I am getting the
> following errors when trying to mount an LVM snapshot:
>
> EXT3-fs: INFO: recovery required on readonly filesystem.
> EXT3-fs: write access unavailable, cannot proceed.
>
> I saw a thread on redhat.com that said a kernel patch is needed.  My

BS.  You are trying to mount a non-clean filesystem on a read-only
LV.  I don't know why your LV is read-only.  You should find out why
it is, make it writable, and run fsck on it.  After that, you should
be able to mount it.

-- 
M�ns Rullg�rd
mru@users.sf.net

Re: [linux-lvm] Re: LVM ext3 support

[Kevin P. Fleming]

M�ns Rullg�rd wrote:

> BS.  You are trying to mount a non-clean filesystem on a read-only
> LV.  I don't know why your LV is read-only.  You should find out why
> it is, make it writable, and run fsck on it.  After that, you should
> be able to mount it.

His LV is read-only because it's a snapshot. That means he took a 
snapshot of a unclean ext3 filesystem, and can't mount it because ext3 
wants to clean it up during the mount and cannot do so.

What is the recommended procedure for doing snapshots of journalling 
filesystems? Do the filesystems have to support snapshots directly and 
"quiesce" themselves while the snapshot is being created?

Re: [linux-lvm] Re: LVM ext3 support

[Jan-Benedict Glaw]

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On Fri, 2003-10-17 11:47:33 -0700, Kevin P. Fleming <kpfleming@backtobasicsmgmt.com>
wrote in message <3F903945.6090109@backtobasicsmgmt.com>:
> What is the recommended procedure for doing snapshots of journalling 
> filesystems? Do the filesystems have to support snapshots directly and 
> "quiesce" themselves while the snapshot is being created?

Either mount the filesystem read-only (or unmounted at all) or patch
your kernel to tell the fs driver when a snapshot is taken...

MfG, JBG

-- 
   Jan-Benedict Glaw       jbglaw@lug-owl.de    . +49-172-7608481
   "Eine Freie Meinung in  einem Freien Kopf    | Gegen Zensur | Gegen Krieg
    fuer einen Freien Staat voll Freier Bürger" | im Internet! |   im Irak!
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Re: [linux-lvm] Re: LVM ext3 support

[anthony mayes]

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How would you suggest making it writable?

-- 
Anthony Mayes
UNIX Server Administration
Southern Illinois University Edwardsville
anmayes@siue.edu

Måns Rullgård wrote:

>anthony mayes <anmayes@siue.edu> writes:
>
>  
>
>>I am running Redhat 9 with kernel 2.4.20-20.9.  I am getting the
>>following errors when trying to mount an LVM snapshot:
>>
>>EXT3-fs: INFO: recovery required on readonly filesystem.
>>EXT3-fs: write access unavailable, cannot proceed.
>>
>>I saw a thread on redhat.com that said a kernel patch is needed.  My
>>    
>>
>
>BS.  You are trying to mount a non-clean filesystem on a read-only
>LV.  I don't know why your LV is read-only.  You should find out why
>it is, make it writable, and run fsck on it.  After that, you should
>be able to mount it.
>
>  
>


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Re: [linux-lvm] Re: LVM ext3 support

[Andreas Dilger]

On Oct 17, 2003  20:33 +0200, Måns Rullgård wrote:
> anthony mayes <anmayes@siue.edu> writes:
> > I am running Redhat 9 with kernel 2.4.20-20.9.  I am getting the
> > following errors when trying to mount an LVM snapshot:
> >
> > EXT3-fs: INFO: recovery required on readonly filesystem.
> > EXT3-fs: write access unavailable, cannot proceed.
> >
> > I saw a thread on redhat.com that said a kernel patch is needed.  My
> 
> BS.  You are trying to mount a non-clean filesystem on a read-only
> LV.  I don't know why your LV is read-only.  You should find out why
> it is, make it writable, and run fsck on it.  After that, you should
> be able to mount it.

Måns, I think you need to read the question more clearly before answering.
This is a snapshot LV, so it is always read-only.  The ext3 filesystem is
"unclean" because it was snapshotted without the VFS lockfs patch in place,
so the ext3 filesystem doesn't know it needs to flush the journal.

Anthony, the patch you are looking for is in the LVM CVS at sistina.

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

Re: [linux-lvm] LVM ext3 support

[AJ Lewis]

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On Fri, Oct 17, 2003 at 01:17:20PM -0500, anthony mayes wrote:
> I am running Redhat 9 with kernel 2.4.20-20.9.  I am getting the 
> following errors when trying to mount an LVM snapshot:
> 
> EXT3-fs: INFO: recovery required on readonly filesystem.
> EXT3-fs: write access unavailable, cannot proceed.
> 
> I saw a thread on redhat.com that said a kernel patch is needed.  My 
> question is where can I get the patch for this kernel, how do I install 
> it, and why isn't this built into the kernel in the first place?  Any 
> other suggestions are welcome.

Looks like you don't have the VFS-lock patch installed. something like
linux-2.4.20-VFS-lock.patch, but i don't know what it would be for
Redhat's patched kernels.

Regards,
--
AJ Lewis
Sistina Software Inc.             http://www.sistina.com
720 Washington Ave, Suite 200     Voice:  612-638-0500
Minneapolis, MN 55414             E-Mail: lewis_NOSPAM_(AT)sistina(DOT)com

Current GPG fingerprint = B8F8 CEC8 9B0B B169 C5E2  8589 867E 54C8 4984 3813
Grab the key at: http://people.sistina.com/~lewis/gpg.html or one of the
many keyservers out there...


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Re: [linux-lvm] LVM ext3 support

[David Johnston]

On Fri, 2003-10-17 at 14:44, AJ Lewis wrote:
> On Fri, Oct 17, 2003 at 01:17:20PM -0500, anthony mayes wrote:
> > I am running Redhat 9 with kernel 2.4.20-20.9.  I am getting the 
> > following errors when trying to mount an LVM snapshot:
> > 
> > EXT3-fs: INFO: recovery required on readonly filesystem.
> > EXT3-fs: write access unavailable, cannot proceed.
> > 
> > I saw a thread on redhat.com that said a kernel patch is needed.  My 
> > question is where can I get the patch for this kernel, how do I install 
> > it, and why isn't this built into the kernel in the first place?  Any 
> > other suggestions are welcome.
> 
> Looks like you don't have the VFS-lock patch installed. something like
> linux-2.4.20-VFS-lock.patch, but i don't know what it would be for
> Redhat's patched kernels.

I've run into this, too.  You have to umount the filesystem before you
make the snapshot, eg:
umount /home
lvcreate -L 1G -n homebak /dev/vg/home
mount /home

With XFS (which I haven't tested), you can run xfs-freeze to commit the
journal without umount, but with ext3 the only way to commit the journal
is to umount the filesystem...
-- 
David Johnston <david@littlebald.com>
Little Bald Consulting, LLC