We are looking to move from NFS and CIFS backup to NDMP. As such we will
purchase FC's for the Filer's and connect through a 1GB SAN. We will run TSM
5.2.2 on AIX 5.2.

We use 3590H, which provides 14MB/Sec and 60GB/Tape Native. We will
configure our Filer volumes at 1TB.

To be honest I am still not convinced with NDMP, despite CIFS being
atrocious throughput.

Has anyone information on the following.

1)  What is the compression ratio per 3590H tape? The volume could contain
500K files.

2) If the 1TB Volume only contains say 500GB, does it store 1TB to tape?

3) How long would it take to backup and restore the above volume, with and
without TOC enabled.

4) When NDMP back's up a file does it store contiguous on the tape? Because
there is potential for many tape mounts to restore one file.

Any other performance data and consideration is most welcome.

Kind Regards

Mike