Differential backup not working

[tanis2000]

I'm trying to do something trivial like a FULL backup on monday with DIFFERENTIAL backups on tuesday-sunday.

This should be the easiest task to do with Backup Exec 9.1 for Windows Server but it seems that each differential backup is doing a backup of all the files each time.

I made two jobs. One that does a full backup on a media set supporting differential time, while the other is a differential based on time and date and done on another media set.

What could be wrong?

[Fidel_Fernandez]

Well I have the same setup here and this is the way I have my setup:

My Full job runs on Mondays at 11:00pm and I selected : FullBackup reset archive bit for method in the Job preferences.

My Diff job runs Tues-Sun at 11:00pm and I selected Differential Changed Files for method in the Job preferences

My Diff jobs will grow as files get changed throught the week which is ok and the more the files get changed the bigger the DIff's, so I guess in theory your final diff can get as big as your Full.

If you make a copy of another job and you make changes to the copy, you will also modify the original job. Make two independent jobs one for your Full and another for the Diff.

[Vidyaj__Patneka]

You have to select the following combinations of Full backup -Differential backup;

1]

Full -backup Files-Reset Archive bit
Differential- Changed files

2]

Full -backup Files-Allow incrementals and Differential using modified time

Differential- using modified time


Do not interchange this sequence.We suggest you to reconfigure a test backup using the above sequence (as in 1) and check the results.



Hope this helps.

[Sagar_Kamat_2]

The differential backups may be as big as full backups if,


1. All the files in the selection list get updated.


2.


http://support.veritas.com/docs/258604


Let the selection list be the same for both full and differential backups.


If the issue remains unresolved, please let us know the about the resources that are being backed up.

[tanis2000]

My configuration is exactly:

- FULL - Backup files - allow incremential and differential using modified time
- DIFF- using modified time

The fact is that the FULL backup is 39Gb and each DIFF is around 20Gb a day, and this is something impossible since the files that get changed each day are surely less than 1Gb.

Is there anything else that could be wrong? The selection list is exactly the same. Does it matter if I'm running two sets of backup each night configured exactly like above, but one on the DAT and the other on an external HDD?

[Zerene_Sangma]

Hello Tanis,

If the Full backup job is 39GB and the Diff is 20 GB then the Diff job has run. If the Diff job fails then it would be backing up the entire 39GB as the FULL backup.

Does the DIFF backup job progressively increase? I would suggest you to perform a test backup backup using Archive bits to isolate the issue. Check if you're getting the same backup size.

[Varsha]

Please update us on this issue.

[Vidyaj__Patneka]

Hope your issue is resolved.Kindly update us if not.