On Thu, 22 Apr 1999, Steve Costaras wrote:
> I have a raid array /dev/md0 on a system here. I am now looking at
> moving some things around and want to rename this to say /dev/md9 or
> whatever. Since this data is mapped (initially) out of the /etc/raidtab
> file and then stored in the raid superblock, is there a way to update
> this WITHOUT loosing data on the device?
>
> Ie, I'm keeping all disks/partitions the same that make up the device I
> just want to change it's offset (to free up 900 to create a boot-raid
> device). Is this possible, and if so, how?
there is no 'safe' way yet to change the number of a persistent-superblock
RAID array. You can do it by taking the array down (stop it), and recreate
with a modified /etc/raidtab. BUT! doing this you lose all protection
against device mixups (for this one single mkraid that is), so you have to
be very careful to have the right partitions mentioned. Especially on
RAID1 and RAID5 the reconstruction starts immediately overwriting what it
thinks to be redundant data ...
but yes, this works. Alternatively there could be a safe 'tuneraid'
utility to do various smaller changes to an array. (one such functionality
would be to change the number of the array, another one could be to make
an array's config 'immutable')
-- mingo
