Re: D1000, Veritas, and Oracle Parallel Server questions

In comp.unix.solaris Allen <allenh_at_starbase.neosoft.com> wrote:

> I'm a DBA and the company I recently started working at is using 2 Sun
> e220 servers hooked up to a D1000 unit running Veritas volume manager
> (also running Oracle 8.1.6 and Solaris 7). Right now Veritas monitors the
> database on server #1 and if it goes down, it brings up the DB on server
> #2.. These sun boxes share the drives in the D1000 where the oracle
> datafiles are installed.
 

> Down the road, we're expecting a huge increase in the amount of data being
> processed and stored in Oracle (24x7), and I suspect we'll need to move to
> a parallel server environment (OPS).
 

> Being a newbie to OPS, I believe I read somewhere that OPS requires raw
> devices. Does this mean we will not be using Veritas volume manager if we
> switch to OPS, or can Veritas handle this? And will the D1000 drives work
> in an OPS environment?

I'm not familiar with OPS, but Veritas does support raw devices as far as the application is concerned. You just don't put a filesystem on your volume.

> Also, I'm a little concerned that the D1000 (which can hold 10 drives)
> only has 1 drive controller. Is this a cause of concern with possible I/O
> contention or is this controller effective when reading/writing to 10
> disks at once?

It's just a SCSI box sitting on a scsi bus (2 if you've split it). It doesn't really have a "controller". You're talking to the drives directly.

It may be a concern for you.

> Another D1000 question - right now we only have 6 drives in it, resulting
> in 3 mirrored pairs in a RAID 5 environment. Are the raid mirrored
> drives

I don't know what that means at all. If you have 3 mirrors out of 6 drives, then you're doing RAID1 or "mirroring" as Veritas would call it. That has nothing to do with RAID 5.

> that big of an advantage in Oracle, or would I be better off with 6
> individual volumes? Since our current D1000 has room for 4 more disks,
> I've requested that they be added as non mirrored drives which would give
> me 7 volumes to play with (3 mirrored, 4 non). Again, does this sound
> feasable with a D1000 that has only 1 disk controller?

You would then have non-redundant data. If you can handle having a disk die, forcing you to recover from backups, then it's possible.

If they're truly mirrors, then all a raw disk gives you is more capacity, not really much more speed.

If they're really RAID5 sets, then it gives you more speed, but at a loss of redundancy.

> Finally, if/when we switch to OPS, I can't imagine why we would need
> Veritas to monitor the status of our database, since if one goes down the
> other parallel servers take over (right?). And if we are forced to switch
> to unix raw devices.. then is our $20,000 Veritas license useless?

You would probably want to use Veritas anyway. It lets you make the "raw devices" redundant on several disks, easily importable by another machine.

-- 
Darren Dunham                                           ddunham_at_taos.com
Unix System Administrator                    Taos - The SysAdmin Company
Got some Dr Pepper?                           San Francisco, CA bay area
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