> NO!! your raid devices are completely messed up at the moment since you've
> been updating the partitions on sda without updating sdb. The disks MUST
be
> resynchronized before you can safely mount /dev/mdxx.
>
> Probably the easiest way to do this is power down /disconnect your sdb
> drive; raid will switch to degraded mode using only the partitions on sda.
>
> Next modify fstab and reboot mounting /dev/mdx partitions (reactivate your
> sdb drive). Now you can raidhotadd the partitions on sdb to your raid
> device to get a fully operative raid system again.
So let me get this together:
0) Make a complete backup in case I fry the thing.!
1) halt the box and disconnect power from sdb.
2) boot the box and modify /etc/fstab to use /dev/md[x] where needed.
3) halt the box and re-connect the power to sdb.
4) boot the box again, this time it will use the new /etc/fstab to mount
/dev/md[x].
What will prevent the /dev/sdb from being used in the RAID reconstruction
after this reboot? Will the superblocks be different and cause the RAID to
stay in degraded mode?
5) use raidhotadd (where is a man page for this found??) to add my sdb to
the raid.
6) All should be ok now?
> Another question: after you created your raid devices, did you create new
> ext2 filesystems on /dev/mdx?
No.
here is what i did:
1) I installed the distribution onto /dev/sda. Compiled in RAID1 support
instead of a module.
2) Next I set my /dev/sdb drive to be partitioned the same way (as in size
and name order) as /dev/sda, using cfdisk (setting the fs types to 'fd' only
on the /dev/sdb[x] and /dev/sda[x] devices that I am using in my RAID1).
Here is the output of
fdisk -l /dev/sda
Disk /dev/sda: 255 heads, 63 sectors, 1116 cylinders
Units = cylinders of 16065 * 512 bytes
Device Boot Start End Blocks Id System
/dev/sda1 * 1 26 208813+ 83 Linux
/dev/sda2 27 1116 8755425 5 Extended
/dev/sda5 27 791 6144831 fd Unknown
/dev/sda6 792 957 1333363+ fd Unknown
/dev/sda7 958 1021 514048+ fd Unknown
/dev/sda8 1022 1085 514048+ fd Unknown
/dev/sda9 1086 1102 136521 82 Linux swap
/dev/sda10 1103 1115 104391 fd Unknown
===========
and fdisk -l /dev/sdb
Disk /dev/sdb: 255 heads, 63 sectors, 1116 cylinders
Units = cylinders of 16065 * 512 bytes
Device Boot Start End Blocks Id System
/dev/sdb1 * 1 26 208813+ 83 Linux
/dev/sdb2 27 1115 8747392+ 5 Extended
/dev/sdb5 27 791 6144831 fd Unknown
/dev/sdb6 792 957 1333363+ fd Unknown
/dev/sdb7 958 1021 514048+ fd Unknown
/dev/sdb8 1022 1085 514048+ fd Unknown
/dev/sdb9 1086 1102 136521 82 Linux swap
/dev/sdb10 1103 1115 104391 fd Unknown
===========
Any idea why /dev/sda2 and dev/sdb2 have different end numbers and blocks??
3) I created a /etc/raidtab with an entry for all the file-systems except /
and swap, I followed the format in the HOWTO for RAID1.
4) umount all /dev/sda's except root and issued a mkraid --really-force
/dev/md[x] for each entry in /etc/raidtab. Waited for the syncing to
complete on all the /dev/md[x]'s.
5) Rebooted the machine and saw that the auto-detection was successfull.
6) Now I'm here...
