Re: adding a disk to a raid(4) array

[mlelstv%serpens.de@localhost (Michael van Elst)]

brook%nmsu.edu@localhost (Brook Milligan) writes:

>Is it possible to reconfigure an existing raid(4) array to, for
>example, add another disk?

Usually not, which is mainly a problem of RAID itself.

You could enlarge a RAID0 concatentation without striping
or add additional RAID1 mirrors. A RAID4 set could also
be expanded. Everything else requires an expensive and dangerous
rebuild of the RAID, where stopping in the middle might leave
you with garbage. And yes some hardware raid controller even
support this.

So what most people do to expand a RAID is to add another RAID,
e.g. if you use a RAID5 with 3+1 disks, then add another 3+1 disks.
And use a volume manager to combine them.

The next problem then is to resize the filesystem so that it will
actually use the new space.

-- 
-- 
                                Michael van Elst
Internet: mlelstv%serpens.de@localhost
                                "A potential Snark may lurk in every tree."