Add disk to stripe set with parity 1

[wattsup]

I was just hired and was doing an initial inventory of our servers. I found that two servers (running NT 4) each with a 3 disk stripe set with parity is almost full. I want to be able to add a hard drive to each set. Is this possible?

Thanks

 

[ShackDaddy]

Yes, back up the entire striped volume(s) and then delete the volume(s). Add another disk, and recreate the stripe set. Once the new volume, with greater capacity, is on-line, restore the data to the volume. There's no way to add a disk to a stripe set 'on the fly'. You have to rebuild the stripe set, regardless of your hardware (unless there's some special new RAID5 technology I'm not aware of). ShackDaddy

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[FilthPig]

With our HP NetRAID cards we were always able to add space on the fly. I would refer to the documentation of whoever the manufacturer of the RAID controller is. Marc Creviere

 

[ShackDaddy]

Interesting, I'd be very interested in knowing, on a technical level, how a new disk gets absorbed into a stripe set. Anyone know off-hand or have any particularly illumining links on the subject?

 

[FilthPig]

Well, when you lose a disk and have to replace it it uses the parity information to rebuild. I would imagine it uses a similar process when you add a disk. Marc Creviere

 

[FilthPig]

Oh, also, wattsup - make sure you add a disk that's the same size and speed as the disks currently in the machine. Marc Creviere

 

[TheLad]

With Compaq servers (same with HP, IBM & Dell to my knowledge), if you want to add a disk, you just add it (has to bee the same size and type as the others) and using SmartStart, you add the new disk to the existing logical volume. The server takes care of the restriping process automatically (takes a few hours depending on the size of the logical volume/amount of disks)

As for increasing the size of an NT partition, I always used Partition Magic. -----------------------------------------------------
"It's true, its damn true!"
-----------------------------------------------------

 

[ag6969]

You didn't specify if the servers where using hardware or software RAID, that's what makes the difference. If software, then ShackDaddy's answer is correct, you have to backup, delete the stripe set, add the disk and reconfigure.
If they are using hardware, check the documentation for the controller, most controllers have this capablility. You just add the disk, use the config program to add the disk to the array.
Either way, backup everything first, I wouldn't even think of expanding an array even on a H/W RAID without backing up first.

 

[thebook]

I have just added 2 more drives to my existing 3-Drive hardware RAID setup on a proliant 1600 with NT 4.0 SP5. Smartstart looked like it re-striped the set...lots of blinking. However, when booted into NT it would hang and then crash about a minute after being logged in. Could not even install the SP again. Any help on this one?


Thanks