Hi, I have a raid 6 consisting of 10 drives, 2x5 sata disks. Each set of 5 behind a port multiplier. The port multipliers/disk/drivers are a bit flaky sometimes and I need to pull the cable between the controller and port multiplier to get the disks recognized sometimes. Now after rebooting I can't assemble the array. mdadm -A /dev/md12, reports that 5 disks are too few to assemble array. One set of (5) disks says that everything is ok when checked with mdadm -E, but the other set says that 5 disks are failed. The first set of 5 disks report this: /dev/sdax2: Magic : a92b4efc Version : 1.1 Feature Map : 0x0 Array UUID : 557d7924:1c547f1c:d878c05d:5a37cfcd Name : 12 Creation Time : Sun Oct 18 22:07:52 2009 Raid Level : raid6 Raid Devices : 10 Avail Dev Size : 1953118176 (931.32 GiB 1000.00 GB) Array Size : 15624941568 (7450.55 GiB 7999.97 GB) Used Dev Size : 1953117696 (931.32 GiB 1000.00 GB) Data Offset : 264 sectors Super Offset : 0 sectors State : clean Device UUID : ac9db196:fc239a13:2a44b03b:aa45055a Update Time : Thu Nov 18 13:17:25 2010 Checksum : d65e4e57 - correct Events : 6 Chunk Size : 256K Array Slot : 5 (failed, failed, failed, failed, failed, 5, 6, 7, 8, 9) Array State : _____Uuuuu 5 failed other 5 disks report this: /dev/sdt2: Magic : a92b4efc Version : 1.1 Feature Map : 0x0 Array UUID : 557d7924:1c547f1c:d878c05d:5a37cfcd Name : 12 Creation Time : Sun Oct 18 22:07:52 2009 Raid Level : raid6 Raid Devices : 10 Avail Dev Size : 1953118176 (931.32 GiB 1000.00 GB) Array Size : 15624941568 (7450.55 GiB 7999.97 GB) Used Dev Size : 1953117696 (931.32 GiB 1000.00 GB) Data Offset : 264 sectors Super Offset : 0 sectors State : clean Device UUID : 2bc9f9dc:efcc4041:8a495b40:ad504353 Update Time : Sat Nov 6 14:56:15 2010 Checksum : 482b7858 - correct Events : 2 Chunk Size : 256K Array Slot : 0 (0, 1, 2, 3, 4, 5, 6, 7, 8, 9) Array State : Uuuuuuuuuu Should I try mdadm -A -f /dev/md12 or do I need to run a create command to get the array up and running? I'm in the process of copying the drives so I have a backup in case something goes wrong with the assembling... /Björn -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html