topic Re: HVD10 striping and mirroring in Operating System - HP-UX

HVD10 striping and mirroring

Nick D'Angelo — Sun, 15 Apr 2001 23:32:46 GMT

All,

We have purchased an HVD10 JBOD with dual controllers connected to an R Class server.

I was wondering if I could stripe and mirror three disks on one of the controllers to the same three disks on the other controller? I am going to be using these three disks for a Progress 8.2c database and in it would make more sense to better utilitize the three spindles for better throughput.

Thoughts/suggestions are always welcome,

Thank you,

Nickd

Re: HVD10 striping and mirroring

Jim Mulshine — Mon, 16 Apr 2001 08:04:14 GMT

You could stripe and mirror your data over the same three disks, but it isn't a good way to protect the data. If one of the three disks crashes then you'll have to do a restore from backup to recover. It would be better if the mirror is placed on separate physical disks. Having two controllers in the HVD10 doesn't change the fact that the mirror copy lies on the same physical disks as the main copy. Striping the data over the three disks, without mirroring, could however be good for performance.

Re: HVD10 striping and mirroring

Pedro Sousa — Mon, 16 Apr 2001 08:13:23 GMT

Hi,
my sugestion is the following:

- stripping is very good for performance (maybe you need to check which stripe size you should use)
- mirror should be used between two different scsi buses! If you are using the same bus, it is a single point of failure, but if you don't have that possibility, mirror is allways a good idea.

good luck.

Re: HVD10 striping and mirroring

Bill McNAMARA_1 — Mon, 16 Apr 2001 09:35:30 GMT

Hi Nick,
you can do this using Physical Volume groups,
see the -g option of the vgcreate.
After creating the physical volume group, you can create the mirrored stripe (effectively raid 1/0) with lvcreate -D y -s g ( Distributed yes and strict on group)

Although it works, I've heard rumours that it's not recommended or supported, but that's for HP to decide, not me!

Later,
Bill

Re: HVD10 striping and mirroring

Patrick Wallek — Mon, 16 Apr 2001 13:32:11 GMT

As far as I know the '-D y' option to lvcreate is supported by HP. They told me about it at one point and sent me some information on how to utilize it.

I use that to "stripe" and mirror all of my data that is on JBOD disk (I have a bunch of Jamaica's) and it works wonderfully. I have had no problems with it. I would highly recommend going that route.