I recently upgraded a server from Fedora 6 to Fedora 14. In addition to the main hard drive where the OS is installed, I have 3 1TB hard drives configured for RAID5 (via software). After the upgrade, I noticed one of the hard drives had been removed from the raid array. I tried to add it back with mdadm --add, but it just put it in as a spare. I figured I'd get back to it later.
Then, when performing a reboot, the system could not mount the raid array at all. I removed it from the fstab so I could boot the system, and now I'm trying to get the raid array back up.
I ran the following:
mdadm --create /dev/md0 --assume-clean --level=5 --chunk=64 --raid-devices=3 missing /dev/sdc1 /dev/sdd1
I know my chunk size is 64k, and "missing" is for the drive that got kicked out of the array (/dev/sdb1).
That seemed to work, and mdadm reports that the array is running "clean, degraded" with the missing drive.
However, I can't mount the raid array. When I try:
mount -t ext3 /dev/md0 /mnt/foo
mount: wrong fs type, bad option, bad superblock on /dev/md0, missing codepage or helper program, or other error In some cases useful info is found in syslog - try dmesg | tail or so
and /var/log/messages shows:
EXT3-fs (md0): error: can't find ext3 filesystem on dev md0.
Does anyone have any ideas of what to try next?