Mike,

We have a very similar environment to you and similar performance problems.
We can achieve 5.5Mb/s backing up our Exchange server but only manage 2.5Mb/s
on the file servers. I suspect this is due to OTM running on the file servers
and the number of small files being backed up.

One thing we have adjusted is the comms. buffer size which does seem to make
some difference. We currently use a value of 256Kb but I may try increasing
this. The parameter can be found in the Registry under the VERITAS key.

Dave.

If you are using the OTM try changing the 'OTM_max_cachsize' (in registry
under software/veritas/nbu/cv/config/) to '0' this will allow dynamic cache
sizing. You probably also have a fragmentation problem if the drive(s) is
90% full.

Another approach to speeding up server performance in general is to balance
I/O. I use Compaq's and these have dual-PCI buses. Balancing NIC/RAID card
placement across both buses will help utilize all of the pc's power (clients
and servers).

(also make sure you are patching you NBU servers and(!) clients with the
latest and greatest patches from veritas.)

-Jon

Michael Weavind wrote:
>System setup.
>
>NT 4 sp3 & 4 (mainly 4) clients runing netbackup 3.2 nt client. Sun
>enterprise servers with Solaris 2.6 and netbackup 3.2 and an Sun
>L11000 library.
>
>Problem - we are seeing very poor performance when backing up some of
>our nt file servers. These servers have between 500 & 750 thousand
>files occupying 80-100Gb (which in most cases is over 90% of the
>available diskspace) , so lots of small files. Under arcserve 6.5
>(using the arcserve agent across the same network) we were getting
>over 3Mb/sec when backing up these servers, yet we barely manage
>1.7Mb/sec using netbackup. Yet with other nt boxes we have seen over
>7mb/s so I know the backed is capable of good performance.
>
>Has anyone else had any problems like these - are there are any
>parameters on the client that can be tuned to improve performance or
>any other suggestions?
>
>thanks
>
>Mike Weavind
>mike@taynuilt.demon.co.uk