2012/7/9 NeilBrown <neilb@xxxxxxx>: > On Sun, 8 Jul 2012 23:47:16 +0200 Alexander Schleifer > <alexander.schleifer@xxxxxxxxxxxxxx> wrote: > >> Hi, >> >> after a new installation of Ubuntu, my RAID5 device was set to >> "inactive". All devices were set to spare device and the level was >> unknown. So I tried to re-create the array by the following command. > > Sorry about that. In case you haven't seen it, > http://neil.brown.name/blog/20120615073245 > explains the background > >> >> mdadm --create /dev/md0 --assume-clean --level=5 --raid-disk=6 >> --chunk=512 --metadata=1.2 /dev/sde /dev/sdd /dev/sda /dev/sdc >> /dev/sdg /dev/sdh >> >> I have a backup of the mdadm -Evvvvs output, so I could recover the >> chunk size, metadata and offset (2048) from this information. >> >> The partially output of mdadm --create... shows this output: >> >> ... >> mdadm: /dev/sde appears to be part of a raid array: >> level=raid5 devices=6 ctime=Sun Jul 8 23:02:51 2012 >> mdadm: partition table exists on /dev/sde but will be lost or >> meaningless after creating array >> ... >> >> The array is recreated, but no valid filesystem is found on /dev/md0 >> (dumpe2fs: Filesystem revision too high while trying to open /dev/md0. >> Couldn't find valid filesystem superblock.). Also fdisk /dev/sde shows >> no partition. >> My next step would be creating Linux RAID type partitions on the 6 >> devices with fdisk and call mdadm --create with /dev/sde1 /dev/sdd1 >> and so on. >> Is this step a possible solution for recovering the filesystem? > > Depends.. Was the original array created on partitions, or on whole devices? > The saved '-E' output should show that. > > Maybe you have the devices in the wrong order. The order you have looks odd > for a recently created array. > > NeilBrown The original array was created on whole devices, as the saved output starts with e.g. "/dev/sde:". I used the order of the 'Device UUID' from the saved output to recreate the order in the new system (the ports changed due to a new mainboard). After the installation I had a degraded array in initramfs, but I was able to simply "exit" the debug shell and the array was accessible. I will now skip the step of creating raid type partitions and try every possible order of devices. Thanks, -Alex -- 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
