[CentOS] Mirror After?

[Les Mikesell]

ML wrote:
>
> If I put a 1TB HD in my server (because they are on sale this week),  
> can I later Mirror to a second 1TB drive without destroying the data  
> on the first?
> 
> On Windows and OS X, I know I can't do this...
> 
> Thoughts?

Partition the disk into one partition of type 'FD' (raid autodetect) Use 
mdadm to create a 2 device RAID1 but specify one device as "missing" 
and mount the md device instead of the disk partition.  Then when/if you 
get a matching drive, create the matching partition and add it to the 
raid with 'mdadm --add'.   Personally, I think this should be the 
default mechanism when installing but you can't do it at all there.

-- 
   Les Mikesell
    lesmikesell at gmail.com