Hi Deepak,

Here is a similar thread. Its quite old but it still holds true.

These limitations are usually on the filer side. Netbackup is just a facilitator for NDMP backups.

https://forums2.symantec.com/syment/board/message?...

I have read that before, but apart from that there is not any kind of tech note available

appretiate if somebody has any link or any document

i have one ongoing issue with NBU and NetApp NDMP BKP. NDMP slow bkp and restores for the specific volume of the NetApp storage

i have told customer the same but he is not ready to listen and asking if there's any concrete document which will explain the same.

somethin so that i can tell him to go for netapp support for this....

pissed off ...  really... need help

Only issues with one volume? Do you backup other volumes from same device that backup ok?

What is the make-up of data on volume? (e.g. size, number of files etc)

Are there any disk issues on NDMP device? We had an issue where performance for one volume dropped dramatically - the length of time trebled from one week to the next - it was eventually determined that there was a 'faulty' disk in the containing aggregate that was being continually thrashed (constantly over 80% utilisation/access) & when this was replaced problem was resolved.

Activity on filer when backup active? NDMP gets a 'back-seat' as far as resources are concerned if there is a lot of user activity.

TechNotes - found a few (altho' they may not be relevant to your situation), there may be more:

DOCUMENTATION: Known restrictions when using Direct Access Restore (DAR) with Network Data Management Protocol (NDMP)

STATUS CODE 20: When trying to back up a stream of larger than 1 Terabyte within an NDMP policy, status 20 (invalid command parameter) is reported and the backup fails.

GENERAL ERROR: NDMP DAR Restore of a single file is too slow.

The volume which is causing issue is 2.2 TB (not sure on no of files)

also on the same controller there are other volumes of size 500G and 600G. on those volumes bkp / restore is wokring fine

only said large volume has issue (slow)

for eg - 10GB files will take 1 Day and 17 Hrs to restore :(

Yes we ar e doing DAR restores, but have also tried without DAR for said problematic volume, all in vain.

not sure if you have already tried these, but check the following TN:

http://seer.entsupport.symantec.com/docs/297476.htm
http://seer.entsupport.symantec.com/docs/283926.htm

I have checked these articles before