----- Daniel Clark wrote: -----

>However in [3] there is anecdotal evidence that for undefined
>reasons,
>this just doesn't work well; however these messages are from 2000 /
>ADSMv3, so I am wondering if anyone has any recent experience with
>this kind of setup in TSM 5.2 or 5.3.

We are using this kind of setup with TSM 5.2. We have run into two
types of problems.

The first problem is that things get really ugly if the storage
pools collectively get larger than the shared disk space.

The second problem is that file volumes are treated like tapes in
many respects. In particular, only one session or process can have
a particular file volume open at a given time. We occasionally have
a client session that slows to a crawl, keeping a file volume open
for hours. This can cause backup stgpool and migration processes
to hang when they want to read the volume involved.

I am hoping to get rid of this setup once we upgrade to TSM 5.3.
I think we will be able to use a single storage pool hierarchy,with
collocation groups used to control sharing of tapes.