Larry,
We have three 9710's that are attached to RS6000's and driven by ADSM using
ACSLS.
See if this helps to explain what is going on:
When you have a 9710 robotic library (or anybody else's robotic library, for
that matter),
you have to have device drivers in the operating system for both the robot,
and the individual drives.
You also have separate SCSI connections for the robot and the individual
tape drives.
So for example with 6 drives in a 9710, you have 1 SCSI connection to the
robot, and 6 SCSI connections to the drives.
When ADSM wants a tape mounted, it sends a request (which I think gets
turned into an RPC call) to ACSLS . ACSLS sends the commands out that SCSI
cable to the robot to mount the tape.
Once the tape is mounted, however, the SCSI commands that actually do the
I/O operations go from ADSM directly through the AIX device drivers, across
the SCSI connections to the individual drives.
So all the robot (and ACSLS) do is physically move the tapes around. They
don't participate at all in the actual data I/O. In fact, once you get a
tape in the drive, ADSM can keep doing I/O to the drive even if you turn the
robot arm off!
If you realize that, it helps explain what IBM and STK have told you (which
as far as I can tell is correct):
You can run a 9710 with ADSM alone, or with ACSLS. If you run it with ADSM
alone, IBM's support for the 9710 will not deal with the fact that you are
sharing the library with another piece of software/hardware. Thus the
requirement for ACSLS.
If you hook up your HP's to the 9710, the only way you could communicate
with the drives in the 9710 is via a SCSI connection from the HP host, and
it's device drivers. So you need some software on the HP that will do the
backup I/O and communicate with the devices across that SCSI connection.
Which means you could either:
* Install an ADSM server (and client) on the HP, which requires its
own data base, etc. as they told you.
This option will turn out to be pretty expensive, and give you 3
ADSM servers to manage.
* Use the Oracle backup utilities to talk directly to the tape drives,
without using ADSM or the robot.
This destroys the advantages of having a robot, and leaves you two
different types of backups you have to administer.
* Install the ADSM client on the HP and send the data to the central
ADSM server which controls the robot.
This puts you right back where you are now, sending your data across
the network.
Have you considered installing a "service network" for your 2 HP'S?
What some people have done is to put a second network card into the ADSM
server and also the other machine(s), creating a "private network" between
just those clients and the ADSM server. Just for those machines, you use
faster network hardware, whatever is required to get the link fast enough.
It's cheaper than upgrading your whole network. Even that alternative may
be difficult with 200 GB Oracle data bases, unless you can do true
incrementals using something like Oracle EBU. But if you could get
sufficient speed that way, it might be better than adding 2 more ADSM
servers (and it's certainly easier to administer.)
Hope this helps.
***************************************************************
Wanda Prather
The Johns Hopkins Applied Physics Lab
443-778-8769
wanda_prather AT jhuapl DOT edu
"Intelligence has much less practical application than you'd think" -
Scott Adams/Dilbert
***************************************************************
*
> -----Original Message-----
> From: Larry Chisesi [SMTP:lchisesi AT COCOMP DOT COM]
> Sent: Monday, October 19, 1998 12:50 PM
> To: ADSM-L AT VM.MARIST DOT EDU
> Subject: STK ACSLS and ADSM
>
> We are looking to share an STK 9710 SCSI library with 10 DLT 7000
> drives. We understand that the ACSLS product from STK enables this. We
> will have a dedicated ADSM server taking 3-4 of the drives for backing
> up clients via a 100 Mb network. We want to directly attach 2 large HP
> servers that have Oracle databases > 200 GB to the STK library so that
> we are not backing them up over the net, going directly to the tape
> drives in the 9710 instead.
>
> I have heard from an IBM rep that we need to have ADSM server licenses
> on these two HP servers, in addition to the ADSM server license for our
> dedicated backup server, and that these Oracle servers have their own
> ADSM databases, manage their own media, etc. Someone else told me that
> the library is managed by the dedicated ADSM server via ACSLS and the
> Oracle servers merely output to the tape drives in the library.
>
> We are trying to create an environment that is easy to administer (who
> isn't!) and works as simply as possible. Does anyone have experience
> with ACSLS in the Unix environment? We will have either an AIX box or
> Solaris system be the dedicated ADSM server. Can you point me to any
> IBM documentation that lays this out, along with licensing requirements?
>
> Thanks!
>
> Larry Chisesi
> CoComp Technical Services
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