Re: RMAN & hardware multiplexing

From: Holger Baer <holger.baer_at_science-computing.de>
Date: Mon, 04 Aug 2003 09:07:51 +0200
Message-ID: <3F2E0647.8010804@science-computing.de>

Joel Garry wrote:
> All:
>
> I was reviewing the 8i RMAN manual, and there is a big warning that
> Oracle does not recommend hardware multiplexing of Oracle backups. A
> brief look at metalink wasn't too illuminating - they think it would
> cause too much disk head movement? I would think hardware
> multiplexing would specifically account for that. What exactly do
> they mean?
>
> Or let me know if I missed something in the metalink RMAN index:
> http://metalink.oracle.com/metalink/plsql/ml2_documents.showDocument?p_database_id=NOT&p_id=131865.1
>
> I'll be doing 8.1.7.4 and 9.mumble on hp-ux and W2K with perhaps
> various cheap raid. Opinions on cheap raid solicited.
>

I think this is the usual warning that hardware as well as software can fail. So if you rely on hardware multiplexing, and if your only copy is on a failed device, or if your failed copy is on a multiplexed device, you're lost. If, on the other hand, you use the duplexing mechanisms of rman, you've made rman aware of the existence of duplicates and still you're using all hardware you can throw at your backup.

My 2c

Holger Received on Mon Aug 04 2003 - 02:07:51 CDT