On Wed, Oct 12, 2011 at 11:37 AM, David C. Miller millerdc@fusion.gat.com wrote:
Not booting from them, but is there a problem with kernel autoassembly on large partitions? I see this in dmsg:
md: Autodetecting RAID arrays. md: invalid raid superblock magic on sde1 md: sde1 has invalid sb, not importing!
But mdadm --assemble /dev/md5 /dev/sde1 works fine after booting. (The array was created with a missing member which hasn't been added yet).
When using mdadm you don't even have to partition a drive if you are using the whole thing. Just make sure the block device is set to GPT in parted if it is not already. After creating the RAID1 get the uuid of the raid by doing mdadm -D /dev/dm5. Then use the following format in the /etc/mdadm.conf to have it auto assemble at boot.
ARRAY /dev/md5 devices=/dev/sd[e-f] uuid=$UUID_FROM_MDADM
Thanks - I already had the raid and filesystem (and data) on a partition - it just wasn't restarting at boot. The above approach with the device names of the partitions seems to bring it up in time to make it work when included in /etc/fstab. That's better than nothing, but I'd really prefer kernel autoassembly because the disks are all in swappable enclosures and I do move things around once in a while. Does that just not work for large partitions? I see that 'cat /proc/mdstat' says 'super 1.0' on this device and none of the others.