On Tue, 20 Oct 1998 13:39:24 -0400, Forrest Smith
<[log in to unmask]> wrote:

>Hey there fellow listers,
>
>I hope someone can help me with this.  I am looking for a fault tolorant
>disk array.  I am in a deal with EMC now but the mother company is mostly
>IBM, so of course I get to see their solution as well.  It looks OK on
>paper and really the only reason I bring it up is because IBM's solution is
>almost half the price.  They have just given the presentation on their SSA
>disk solution and now I'm confused.  Does anyone know if HP will support a
>machine with SSA IBM disk on it? Or what the ramifications of this is.  I
>want EMC but 200k is 200k.  I need you listers to help me justify that.
>
>Forrest.

Several things:

1. HP WILL support customers with SSA attached to both HP3Ks and
HP9Ks, despite what some people have posted (they did, however,
qualify that their information was old). If you need names & numbers,
then contact me offline.

2. SSA disks will correctly interact with all HP diagnostic tools
including the CE utilities, as well as HP predictive support.

3.  The IBM VSS (If that is what IBM is touting, instead of their 7133
product)) will NOT work on the HP3000.  I know this, because their VSS
R&D people contacted me to help them with a port.

4. There are other SSA products out there that are not manufactured by
IBM that offer additional features, price-points, and configuration
options for HP environments.  These include:
 - External cache, SSA hubs, non-IBM subsystems, different SSA host
adapters.

5. If you need features, buy EMC.  If you need pricing or performance,
go with SSA.

6. Be careful about any representations with SSA performance on
MPE/iX.  On the HP-UX side, it is pretty easy for SSA to double or
triple performance of Nike, EMC, or Jamaica.  On the 3K, because how
the O/S just hates to go to disk, you *might* see little performance
gain.  I could go into this in detail, but the information is very
system-specific.  I don't want to say that your IBM salesrep might be
misleading you on performance expectations, but you need to talk to
somebody who really knows both SSA and how it works with MPE/iX.
There aren't a lot of them out there.

7. (here comes a small plug)  Check out our web site for additional
HP-specific information on SSA.  http://www.compass-corp.com

8. You might also check out the article I wrote for the HP3K newswire
a few months ago, it has some good stuff in it.

9. HP CSY spent over a month exercising and testing a large SSA
configuration on a 9x9.  They tested both the IBM 7133, as well as our
own (non-IBM) SSA disk subsystem.  Both subsystems passed their tests,
after a few firmware changes were made to the SSA interface adapter.

If you want more information on this, then I'll also pass it on to you
offline.


David A. Lethe
Compass Corporate Systems
972-208-3660