[CentOS] Linux Software RAID 1 - Unequal Sized Hard Disks

Thu Oct 18 16:58:42 UTC 2012
Manish Kathuria <mkathuria at tuxtechnologies.co.in>

On Thu, Oct 18, 2012 at 9:25 PM, Bowie Bailey <Bowie_Bailey at buc.com> wrote:
> On 10/18/2012 11:29 AM, Manish Kathuria wrote:
>> Has anyone created or rebuilt a Linux Software RAID having mirrored
>> partitions on unequal sized hard disks ? There is  a CentOS 5 server
>> having two 400 GB hard disks with five mirrored partitions (software
>> RAID 1) and one of the hard disks is dying. Since new 400 GB HDDs are
>> not available here, we are exploring the possibility of replacing the
>> faulty hard disk with one of a higher capacity (500 GB or more). And
>> once it is fully replicated, we plan to replace the other 400 GB HDD
>> also with another hard disk of the same higher capacity.
>> Just want to know if anyone has done something similar and what are
>> the chances of success (or data loss) ?
> I've done this with a 3-drive software raid 1.  It originally had 750GB
> drives which I replaced with 1TB drives.
> Swapped them out one by one configuring them with the exact same
> partition structure as the others and allowing each one to resync before
> continuing.  Once they were all in, I resized the filesystem (ext3) to
> take advantage of the extra space.
> --
> Bowie

That sounds perfect. Did you create the new partitions manually using
fdisk / sfdisk ? I guess that can take care of the logical partitions.