Resizing/growing RAID partition

dadevilx · 03-21-2009, 01:04 PM

My RAID-5 array consists of the first partition of 4 identical disks and is formatted as XFS (no LVM). This array is running out of space and I'm trying to resize it. The disks all have 2 partitions on them (md0 for the first partition and md1 for the second).

This is what one of my disks look like:

Code:

Disk /dev/sdb: 1000.2 GB, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x00000000

   Device Boot      Start         End      Blocks   Id  System
/dev/sdd1               1       97281   781409601   fd  Linux raid autodetect
/dev/sdd2           97282      121601   195350400   fd  Linux raid autodetect

Basically I want to grow the first partition and shrink (or delete and add probably) the second, which can be deleted if necessary. However, I haven't found any method of growing the first partition. Is it even possible? (without rebuilding the array 4 times)?

mesiol · 03-22-2009, 03:41 AM

Hi,

from my point of view there is no secure way to resize your partitions without the risk of data loss. The problem is, that your RAID has checksum information distributed over all disks, so i'm not sure if they will get corrupted when doing changes on partition level.

The secure way will be:

- create a fullbackup (or better two)
- recreate the RAID with new disks
- add LVM on top of RAID to prevent from the same problem in future

Yes i know there are dozens of tools for resizing and repartitioning, but the all have a risk to loose data and they are made to resize physical OS partitions and not RAID partitions.