On Mar 8, 2006, at 7:25 AM, John Bremer wrote:

Greetings,

We've been using TSM with NDMP for over a year, and while we want our
customers to use our service rather than Legato (the predecessor),
there are some limitations:

(1) There are situations where TSM (or NetApp/NDMP) does not
translate certain file/path names properly, and TOC builds fail.  We
have been working with IBM quite a lot on this, and have resolved
*most* issues;

(2) TOC loads on the TSM server are *excruciatingly* slow.  We have
thrown all the hardware and memory we can at the server, and some TOC
loads still take 4 hours (yes, that is not a typographical
error).  Granted these are multi-TB volumes with millions of files,
still there should be a better way to get the TOC records from disk
to database.  That's another problem we have open with IBM, and we
are working with their performance people.

(3) We recommend defining as many virtual mapping points as possible:
volume restores can be done in parallel, and above mentioned TOC
loads are quicker.  It adds another level of administration, but no
big deal.

We recently restored a 3.3TB volume which took about 29 hours, using
one 9940B drive.

Overall we are happier with TSM using NDMP than backing up these
large filers over TCP, through a TSM backup client (though file level
restore was/is a lot better there).

John

Hi John,

you mention that overall you are happier with the TSM using NDMP
rather than TCP. Could you expand on that for me? We're looking to
perhaps use NDMP on our NetApp farm but would love to get a pro/con
feel going before committing the resources.


Thanks very much


Jason

--
Jason Lee
DreamWorks Animation
(818) 695-3782