How do I grow a raid 5 system?

[n2jesus]

Hi all,
One of our servers has a sata raid 5 on an adaptec raid controller. Within a year or so I will need to make the hard drive space bigger.

I'd like to think that it is as simple as replacing a hard drive with a bigger drive one at a time, let the raid rebuild, then replace another drive. Then repeat until all the drives have bee replaced. At the end you have twice the volume and the raid is using it all.

I'm guessing it's not that easy though, so how do you do it without backing up everything, build a new system and restoring?

Thanks for any advice,

Jim

 

[Jotaerre]

Actually is that simple, if you comply with 2 conditions:

1) you substystem MUST supoport on-the-fly volume grown. I know that the Engenio ( SUN/STK ) discs support that.

2) You O.S. MUST support the same feature. This is simple if you have a LVM live Veritas VxVm or Solaris/AIX/HP-UX bundle LVM's managing the volume you're refferring to. If you're running Windows, and your disk is a Dynamic, you're godd, otherwise, you should consider upgrading it to dynamic. I know there is a procedure to grown up basic volumes without any LVM software, ut i would not try it on a production environment with a 100% valid backup, and a huge maintenance window.

If you comply with these 2 conditions, you're going to grown up you volume with just a pair of clicks and commands. Otherwise, will be a backup, format, and restore operation.

There are other possibilities, like mirroring the volume to a bigger device (if your LVM supoprts that), and promoting the mirror to primal, and breaking the mirror, and many others...

Cheers