Never mixing NDMP and non-NDMP backup in the same media for NetWorker

The following are the limitation of NDMP backup with NetWorker.  You can find these in admin guide but most ppl tend to skip them.  It will be a nightmare when you find out data cannot be recovered.  Some of these limitation possibly apply to other backup solution as well.

For pure NDMP backup (backup to NDMP devices.  that is, FC tape drive presented to NAS), make sure you have non-NDMP backup sent to different pool including index and bootstrap.  The same applied to cloning.  So media written by NDMP devices should not be accessed by non-NDMP devies.  It is not possible to save data from any NAS filer to an tape device using standard NDMP and then write non-NDMP data to the same tape volume.  You will have issue during recovery.

NDMP and non-NDMP savesets can be saved on the same volume only if the NDMP backups to that volume were written using NDMP-DSA (NAS data backup to device presented to Storage Node / NetWorker server).

There is an old kb article from Powerlink to explain it.
"When non-NDMP backups are written to tape, the backup is written directly to the tape by NetWorker in it's own proprietary format. When NDMP and non-NDMP data is written to the same tape, the file marks get out of order and as a result the restore cannot position the tape correctly to find the data image.
Fix: Ensure that NDMP data be backed up to it's own separate pool to prevent NDMP recovery and scanner problems."

Keep in mind when migrating your NAS.  If you plan to migrate to different vendor, for ex, NetApp to BlueArc, make sure you no longer need the backup on the old NAS (in this ex, NetApp) or you keep your old NAS somewhere in case recovery required.  NetApp and BlueArc are on different OS.  That's why you cannot recover NDMP backup by NetApp to BlueArc.

Also, make sure you have a copy of the index saveset.  scanner -i does not work for NDMP backup.

For full details of limitation and other requirements of NetWorker NDMP backup, please consult EMC support or refer to EMC documentation.