expanding raid 5 array

[jamesj]

Hello blessed linux gurus!

I had a 3ware 9650 raid controller card running a raid 5 array that contained (4) 1TB disks. The array used a single ext3 partition and provided about 2.7 TB's of storage for my server.

The time came when I needed to expand this array by adding an additional disk. I used the 3ware 3dm web based raid controller management tool and added the additional drive. The migration, as they call it went fine about 12 hours and was successfully added. I can see the drive in the web software and the array size is correct.

The problem is that the operating system (CentOs5.3) does not see the size increase properly, the disk space remaining has stayed the same.

do i have to repartiton?
if so what is the best method, to keep data intact
it also should be noted that the array is only storage, so no operating system is installed on this array

thank you

[HROAdmin26]

Method 1)

- Sure thing - no risk.
= Backup your data, umount volume, delete partition, create new larger partition, format filesystem, mount volume, restore your data.

Method 2)

- Will lose data if you're not careful/don't know what you're doing and no guarantees.
= Backup your data.
= Umount volume.
= Use parted to delete old partition and create new larger partition. *Do not* format during this operation. Parted is needed to manipulate a GPT partition - don't use fdisk.
= "Grow" filesystem using resize2fs command.
= Mount volume and cross fingers.

* Notice that for either method, you should backup the data, so I would go with Method 1.