On May 14, 2009 23:37 -0400, Robin Humble wrote: > one problem we came across was that ext3/ldiskfs hard-codes the device > name of the external journal (eg. /dev/md5 or /dev/sdc1 or whatever) > into the filesystem. > that means that when you failover OSS's it will look for /dev/whatever > on the failed-over node, and won't mount if it can't find it. > so you need non-intersecting namespaces of journal devices within an OSS > pair, so that each regular and failed-over RAID5/6 can always find its > correct journal device. > I didn't manage to get ext3/ldiskfs to be sane and use UUID's instead of > hardcoded device names :-/
There is a "journal_device" mount option for this. We'd like to make mount.lustre find this device automatically, but it hasn't been fixed yet. See bug 16861. > presumably you could also tune2fs to rename or delete the external > journal as part of a failover, but that's a horrible hack. No, that will potentially lose some data, since ext3 considers data written to the journal as "safe" Cheers, Andreas -- Andreas Dilger Sr. Staff Engineer, Lustre Group Sun Microsystems of Canada, Inc. _______________________________________________ Lustre-discuss mailing list [email protected] http://lists.lustre.org/mailman/listinfo/lustre-discuss
