[Lustre-discuss] external journal and udev problem

[Andreas Dilger]

On Aug 19, 2008  14:59 +0200, Philippe Weill wrote:
> I  put the journal on LVM over multipath  for my OSTs
> 
> formating the OST was made with
> 
> mkfs.lustre -v  --reformat --fsname=datafs --ost  --mgsnode=10.0.0.1 
> --mgsnode=10.0.0.2 --failover=10.0.0.3 --mkfsoptions="-E stride=64 -E 
> stripe-width=9 -J device=LABEL=JNL_OST0_DATA -i 131072" /dev/mpath/ost0_data
> 
> 
> and now I'm fighting against udev since external journal device
> major and minor number seem to be hard coded in the file system
> 
> and change on reboot
> 
> [root at ciclad-io3 rules.d]# tune2fs -l /dev/mpath/ost0_data
> tune2fs 1.40.7.sun3 (28-Feb-2008)
> Filesystem volume name:   datafs-OST0000
> Last mounted on:          <not available>
> Filesystem UUID:          7507ef98-4475-4612-a24b-fb7b0712ea42
> [...]
> Journal UUID:             41f9f23d-b23b-4bec-b694-68bfca9d35c7
> Journal device:           0xfd19
> Default directory hash:   tea
> Directory Hash Seed:      b2550fed-3ffe-4f13-ab8e-a5de49ef9fec
> 
> [root at ciclad-io3 rules.d]# ls -l /dev/mapper/JNL_SUMO1-jnl_ost0_data
> brw-rw---- 1 root disk 253, 23 Aug 19 14:15 /dev/mapper/JNL_SUMO1-jnl_ost0_data
> 
> trying with tune2fs to change the device doesn't seem to work
> or i don't used the good syntax
> 
> [root at ciclad-io3 rules.d]# tune2fs -J 
> device=/dev/mapper/JNL_SUMO1-jnl_ost0_data /dev/mpath/ost0_data
> tune2fs 1.40.7.sun3 (28-Feb-2008)
> The filesystem already has a journal.

This is only to add the journal device to the filesystem.

> what solution could you propose to recover my filesystem

What you are looking for is the mount option "-o journal_dev" to change
the journal device.  See also bug 16140 for a patch related to this.

Cheers, Andreas
--
Andreas Dilger
Sr. Staff Engineer, Lustre Group
Sun Microsystems of Canada, Inc.