Hi,  there are some flowchatrs on the NDMP manual that explains how to tune NDMP backups and restores. Please, see emc218290.   Gustavo Barreto.
I have an SR open at the moment where I've enquired about what the possibilities are for improving the throughput of NDMP backups on DART 5.6. So far EMC have confirmed that 4 concurrent NDMP streams are supported where this means one stream per filesystem. Multiplexing the streams to a single tape device should also be possible.  We are using EMC Networker 7.4.x at the moment for the NDMP backup agent with a Fibre attached library. One tape drive is currently visible to the NS20.  Does anyone else out there have any experience of this or any ideas which elements of the DART and Networker config are involved in getting this concurrency to work. I believe the options are under the PAX and NDMP facilities of the DART server params and various of the parallelism options in Networker. We have tried a number of these but can't seem to get more than one filesystem to stream at a time. This is an issue as some of the filesystems have many small files and seem to be restricted by filesystem metadata access rather than raw throughput.  The intention in the longer term is to make another tape drive visible to the Celerra and use both multiple drives and NDMP stream multiplexing (2x2).  Anyone? [IMAGE]
NDMP Multiplexing and Concurrency