NDMP Differential Backup on NetApp
i make backups from a netapp filer FAS2040 , NetApp Release 8.1.2 7 .
I make one full backup in 4 weeks, and one differential backup per day. The full backup has 6 TB on size.
The differential backup has on the day after full backup 20-30 GB, but is growing day by day.
On the end of month i have sometimes one terabytes of data in a differential backup for one day. This is not possible.
I use netbackup server 6.5.4. on solaris 10. I use ndmp over network (not direct write to tape).
I use NDMP also for sun/oracle open storage zfs box. Here is all ok.
Where can be the problem ?