There ain't no magic bullet for that question.

You have to factor in a bunch of things;
- The size of the backup windows for the Oracle/Domino server
- how much the Oracle/Domino/other server windows overlap.
- The amount of Oracle/Domino data you need to backup in the windows.
- amount of disk stgpool (can you backup the entire window)
- number of available tape drives (how many can you spare at any given
time)
- type of disk (can it handle a full write load from Gigabit Ethernet)
- if you are confident the Oracle/Domino servers can stream to the TSM
server at the speed of the tape drives (15MBytes/sec)

Judging from the number of tape drives it would make sense to keep
streaming the Oracle/Domino data directly to tape. This would avoid a
potential bottleneck writing to the disk pool (unless you have very fast
disk subsystem) and the 15MB/sec would allow most large database dumps
in a few hours.

I would look at keeping a separate Gigabit segment for the database
servers. It won't take too many connections on the main pipe to take a
big chunk of it, and if you stream to tape you want the LTO drive
buffers to be well fed (a potential performance issue).

Cheers, Suad
--

On Tue, 2002-11-19 at 21:45, HEMPSTEAD, Tim wrote:
> Hi,
>
> We are replacing our existing TSM server with a new one and I have a
> question about storage pool configuration.
>
> Currently our TSM server is running on the same RS6000 as our main Oracle
> databases using a STK L700 tape silo connected directly to the RS6000.  The
> TSM server also backs up another RS6000 running Oracle and a couple more
> running Domino over a gigabit network.  The Oracle data and Domino database
> data from these servers goes straight to tape whilst file-level data and
> Domino transaction log data go via a disk storage pool.
>
> We are now going to use a separate RS6000 server running TSM 5 with an IBM
> 3584 silo with 8 LTO drives.  This will be connected to the other servers
> via the gigabit lan.
>
> Would it be better to keep some of the data going straight to tape or would
> I be better to use an intervening disk storage pool for all of the data and
> then use multiple LTO drives to migrate to tape?
>
> Thanks
>
> Tim
>
> --
> Tim Hempstead, thempstead AT slb DOT com
> Unix Technical Specialist
> SchlumbergerSema
>
>
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