On Friday February 13, marcus@quintic.co.uk wrote: > [excuse strange formatting - posting from a new news client] > I have a problem trying to replace a failed drive in a RAID1 setup > under Debian (woody). > > Background: I have a 2 disk mirror, RAID 1 setup. It is made up of > two 180Gb Western Digital WD1800JB drives. Both are partitioned as: > > Partition Table for /dev/hda > > First Last > # Type Sector Sector Offset Length Filesystem Type (ID) Flags > -- ------- -------- --------- ------ --------- ---------------------- --------- > 1 Primary 0 4000184 63 4000185 Linux raid autode (FD) Boot (80) > 2 Primary 4000185 5992244 0 1992060 Linux swap (82) None (00) > 3 Primary 5992245 351646784 0 345654540 Linux (83) None (00) > > > Partition Table for /dev/hdc > > First Last > # Type Sector Sector Offset Length Filesystem Type (ID) Flags > -- ------- -------- --------- ------ --------- ---------------------- --------- > 1 Primary 0 4000184 63 4000185 Linux raid autode (FD) Boot (80) > 2 Primary 4000185 5992244 0 1992060 Linux swap (82) None (00) > 3 Primary 5992245 351646784 0 345654540 Linux (83) None (00) > > Output of /proc/mdstat (when both devices are running): > > Personalities : [linear] [raid0] [raid1] > read_ahead 1024 sectors > md1 : active raid1 hdc3[1] hda3[0] > 172827200 blocks [2/2] [UU] > md0 : active raid1 hdc1[1] hda1[0] > 1999936 blocks [2/2] [UU] > unused devices: <none> > > Both raid devices have ext3 filesystems on them. > > The problem: hda has now failed, and I have tried to put in a new > drive. However, when the failed drive is replaced with the new > drive, the raid device md1 will not restart and produces the > following errors: > > Feb 12 14:09:59 bart kernel: md: invalid raid superblock magic on hda3 > Feb 12 14:09:59 bart kernel: md: hda3 has invalid sb, not importing! > Feb 12 14:09:59 bart kernel: md: could not import hda3! > Feb 12 14:09:59 bart kernel: md: autostart hda3 failed! > Feb 12 14:09:59 bart kernel: EXT3-fs: unable to read superblock Looks like you are trying to use 'raidstart'. Raidstart is broken by design. It doesn't work. You could try mdadm... > > whereas, the md0 device auto-recovers - presumably because the > auto-detect flag is set and the kernel is dealing with the rebuild: > > Feb 12 14:09:59 bart kernel: md: linear personality registered as nr 1 > Feb 12 14:09:59 bart kernel: md: raid0 personality registered as nr 2 > Feb 12 14:09:59 bart kernel: md: raid1 personality registered as nr 3 > Feb 12 14:09:59 bart kernel: md: md driver 0.90.0 MAX_MD_DEVS=256, MD_SB_DISKS=27 > Feb 12 14:09:59 bart kernel: md: Autodetecting RAID arrays. > Feb 12 14:09:59 bart kernel: [events: 00000000] > Feb 12 14:09:59 bart kernel: md: invalid raid superblock magic on hda1 > Feb 12 14:09:59 bart kernel: md: hda1 has invalid sb, not importing! > Feb 12 14:09:59 bart kernel: md: could not import hda1! > Feb 12 14:09:59 bart kernel: [events: 000000ce] > Feb 12 14:09:59 bart kernel: md: autorun ... > Feb 12 14:09:59 bart kernel: md: considering hdc1 ... > Feb 12 14:09:59 bart kernel: md: adding hdc1 ... > Feb 12 14:09:59 bart kernel: md: created md0 > Feb 12 14:09:59 bart kernel: md: bind<hdc1,1> > Feb 12 14:09:59 bart kernel: md: running: <hdc1> > Feb 12 14:09:59 bart kernel: md: hdc1's event counter: 000000ce > Feb 12 14:09:59 bart kernel: md0: removing former faulty hda1! > Feb 12 14:09:59 bart kernel: md: md0: raid array is not clean -- starting background reconstruction > Feb 12 14:09:59 bart kernel: md: RAID level 1 does not need chunksize! Continuing anyway. > Feb 12 14:09:59 bart kernel: md0: max total readahead window set to 124k > Feb 12 14:09:59 bart kernel: md0: 1 data-disks, max readahead per data-disk: 124k > Feb 12 14:09:59 bart kernel: raid1: device hdc1 operational as mirror 1 > Feb 12 14:09:59 bart kernel: raid1: md0, not all disks are operational -- trying to recover array > Feb 12 14:09:59 bart kernel: raid1: raid set md0 active with 1 out of 2 mirrors > Feb 12 14:09:59 bart kernel: md: updating md0 RAID superblock on device > Feb 12 14:09:59 bart kernel: md: hdc1 [events: 000000cf]<6>(write) hdc1's sb offset: 1999936 > Feb 12 14:09:59 bart kernel: md: recovery thread got woken up ... > Feb 12 14:09:59 bart kernel: md0: no spare disk to reconstruct array! -- continuing in degraded mode > Feb 12 14:09:59 bart kernel: md: recovery thread finished ... > Feb 12 14:09:59 bart kernel: md: ... autorun DONE. > > >From everything I have read, all I should have to do is replace > the drive when it fails with a correctly partitioned spare, > reboot. Wait for the raid to autostart (in degraded mode) and > raidhotadd the partitions back in to get them resynced. Is this > correct? If not, where am I going wrong? Well, you could set the partition type of hdc3 to be "Linux raid autodetect" and then md1 would work much like md0. Or you could get mdadm and: mdadm --assemble /dev/md1 /dev/hdc3 mdadm /dev/md1 --add /dev/hda3 http://www.kernel.org/pub/linux/utils/raid/mdadm/ 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
