I've had this same problem, and I tracked it down to one of two things.
Bad tape or drive errors. In my case I have a bad drive. 
After disabling the tape drive, I've had no more errors. It was just
replaced under our maintenance agreement.

-----Original Message-----
From: Legato NetWorker discussion [mailto:NETWORKER AT LISTSERV.TEMPLE DOT EDU]
On Behalf Of Terry
Sent: Friday, June 30, 2006 2:43 AM
To: NETWORKER AT LISTSERV.TEMPLE DOT EDU
Subject: [Networker] NDMP Errors

Hi, 

I have a problem with NDMP backups and I wonder if anyone can help. 

I have a Netapp Filer running Ontap 6.4.3 and NDMP v3. I am backing this
Filer up with Legato Networker 7.21 to a Tape Library with LTO2 Drives. 
Periodically some savesets within a savegroup will fail with the errors
:

nsrndmp_save: Data server halted: Out of memory error: null Save session
closed with NW server successfully
nsrndmp_2fh: Received the ABORT message
nsrndmp_2fh: interrupted, exiting the File History merging...
nsrndmp_save: backup failed.
nsrndmp_2fh: nsrndmp_2fh aborted

Howerver this error is very intermiitent and won't appear for some
weeks. 
It appears to be random about which particular savesets are affected. 

Any help gratefully recieved. 

Thanks.

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