Good question Joni,

        Our NetApp admins are very hot&heavy to get us to use NDMP for
our filer backups, as opposed to the "backup the NFS/CIFS mount" way we
are currently doing it. Because of CIFS slowness, on Windows q-trees the
backups take way too long. 

        I totally agree that the NDMP backups and restores will be
faster, but that improvement doesn't come without some tradeoffs.

        Your post highlights one of the reasons I'm reluctant to switch
to NDMP. These are the things about NDMP that make me nervous. They may
be unfounded or wrong, so anybody feel free to jump in and correct me: 

        - Need for attachment between the NetApp and a tape device. Yes
it can be resolved with I-SCSI, facilitation of FC connections or SCSI
lines, or purchasing tape drives, but it's an added expense to our
current environment.
        - As far as I can see, there is no way to make the second copy
(short of doing a second NDMP dump to a different storage pool/TSM
server), so it compromises our DR ability.
        - With NDMP, we go back to the full/diff/incr backup system,
meaning we will have to do periodic full backups which will retain more
data in TSM. On some of these large volumes with long retentions, this
could be a LOT more data in TSM depending on how often we do a "full".
        - TSM currently only supports NDMP at the volume level. On
volumes were we have multiple Q-trees requiring different data
retentions, there is no way to separate them. You have to keep the whole
volume for longest retention.

        Our NetApp admins point to other backup solutions (i.e. bakbone)
that seem to be ahead of TSM in NDMP support and they want to use those
products, but I don't want to support another backup application....

        Like I said, I may be totally off-base here so feel free to
chime in and tell me I'm wrong.

Ben