Adding a disk to RAID

[Bruce Ordway]

Hi, a friend of mine has an HP 10.20 box with RAID, I don't know what level. He said he needs to add disk space & neither one of us has done this before so we're both brushing up on the subject. I have one question & I can't seem to find any references. Is there a limit of number of disks in a RAID 5 configuration? I'm thinking that at some point, there wouldn't be enough room for parity info.
Any reference material on RAID and HPUX that you really like?

[Vincent Farrugia]

Hello,

If you tell us what the RAID box is, and what server, we can tell you more clearly, but here goes. Usually, RAId boxes allow for increase of harddisks. Not only that, they allow this ONLINE, which means you insert the disk, and the harddisk is rebuilt with the remaining LUN automatically.

There is no limit as to what number of disks you can put in RAID 5 in theory. Remember that RAID 5 implements distributed parity, so I can't see what you mean by "not enough room for parity info".

Tell us what RAID box and what server is it and we will tell you more clearly.

HTH,
Vince

[Bruce Ordway]

Distributed parity? Just goes to show I don't know much about RAID. Anyway I don't know the details about my friends system. He just asked me about adding disk space to RAID & I had never done it on a UNIX machine. So I'm just reading up on RAID for general interest. Still looking for more good reference material.

[Bill Hassell]

RAID is a concept that is incorporated into a disk array. HP-UX (10.20) does not control the arrangement of disks in an array. Some manufacturers provide support tools that can be used to configure these arrays, other manufacturers use a terminal or front panel to configure the disks. Without any information about the model of the disk array, there is little to provide as far as how to proceed.

[Richard Steven]

Not to sound unhelpful but people usually use RAID as it protects valuable data. If you and your friend don't know what it is or how it is set up I would advise that you at least get an engineer to talk you through adding the disk.

http://www.google.com/search?hl=en&ie=UTF-8&oe=UTF-8&q=raid+
http://www.acnc.com/04_01_00.html