At 02:54 PM 5/23/97 CDT, [log in to unmask] wrote:
>     We currently have two systems a (959/400 and a 957).  We are
>     using Shareplex to shadow from the 959 to the 957.  Soon we will
>     be getting rid of the 957.  The question comes in for data
>     redundancy and high availability do we:
>
>     1. Use Shareplex to shadow to the same system?
>

Yes, you can do this but mirroring probably makes more sense.

>     2. Get rid of Shareplex and move to mirrored disk?

I would be inclined to mirroring for the production data and using
RAID arrays for the system volume set.

>
>     3. Use image logging?

I'm not sure that this is a particularly good idea due to the time it
takes for recovery and the operational hassle.

>
>     4. Some combination of the above?
>
>     Any thoughts anyone has on this would be greatly appreciated.
>
>     Thanks,
>
>  ---------------------------------------------------------------
>  Barry Durand      "The opinions expressed in this
>  Systems Engineer II    email are not necessarily the
>  Gulf South Health Plans    opinions of my employer"
>  [log in to unmask]
>  ---------------------------------------------------------------
>
>

Barry,

The approach to take is one of "What will give me the highest
availability for the lowest cost both in terms of money and operational
headaches".

You didn't mention how much disk you have.  I assume that you are
under the 50 gigabyte limit, which is about the point at which HP
starts directing their customers to consider mirroring.

If I had a magic wand and I was in your environment, I would implement
mirrored disk and disk array as mentioned above.


Bill Lancaster
Lancaster Consulting