[TriLUG] RAID Recover after losing 1 disk in RAID-1 setup

[Brian Daniels]

On Fri, Nov 05, 2004 at 10:25:18AM -0500, Brian Weaver wrote:
> 
> I'm not very familiar with software raid on Linux so I could not give
> him the commands he needed over the phone or via e-mail. Does anyone
> know the appropriate steps/commands to get him back on the correct
> track?
> 

I'm only familiar with RedHat/Fedora, but the process should be similar:

He needs to install a new drive and partition it with equal or larger 
partitions than the existing drive it is mirroring.  These partitions need to 
be set to type 'fd' Linux Raid Autodetect.

He can then add the partitions to the array with the raidhotadd command:
raidhotadd /dev/md0 /dev/hdc1
which would add partition 1 on drive hdc to the md0 raid device.  He'll need 
to look at his /etc/raidtab to see which partitions were in each array.

He needs to be careful and make sure that he gets the partition sizes 
correct and adds them to the right raid devices. 

Doing a 'cat /proc/mdstat' will show the status of the array and the 
rebuild process.

--Brian

-- 
Question with boldness even the existence of a god;
because if there be one he must approve of the
homage of reason more than that of blindfolded fear.

--Thomas Jefferson, Aug. 10, 1787


Brian Daniels                  bitmage at bellsouth.net
      http://www.eviloverlord.net