On Thursday August 7, arekm@pld-linux.org wrote: > Hi, > > I have two raid 5 partitions - md0 (as for root fs) and md1 (for /home). > ... > [root@perfo arekm]# mdadm -D /dev/md0 > /dev/md0: > Version : 00.90.00 > Creation Time : Tue May 4 09:37:53 1999 > Raid Level : raid5 > Array Size : 9960064 (9.50 GiB 10.20 GB) > Device Size : 4980032 (4.75 GiB 5.10 GB) > Raid Devices : 3 > Total Devices : 4 > Preferred Minor : 0 > Persistence : Superblock is persistent > > Update Time : Thu Aug 7 12:48:34 2003 > State : dirty, no-errors > Active Devices : 2 > Working Devices : 0 > Failed Devices : 3 > Spare Devices : 0 "Spare Devices : 0" is the problem. It thinks there aren't any spares, even though there obviously is one... The code in the kernel for keeping these counters up-to-date is very fragile and I'm not surprised that it occasionally gets things wrong. > > Both arrays was created under some 2.2 kernel. Resync doesn't happen on 2.5.25, too. > 2.5.25 is ancient! 2.6.0-test2 should be able to assemble it (it ignores those counts) but there is some data corruption bug that I am hitting in 2.6.0-test2 that could well be raid5 related, so I'm not sure I would recommend that. I could probably knock up a patch to 2.4.21 in a couple of days that corrects the counts when an array is assembled. Alternatively if you can boot off a rescue disk, then mdadm -C /dev/md0 -l5 -c 32 -n 3 /dev/sda2 /dev/sdb2 missing mdadm /dev/md0 -a /dev/sdc2 should get you out of trouble. NeilBrown - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
