Daily Differential Backups

[JWorth]

Hello,

I am using Backup exec 11D SP4 and have noticed something strange about the Differential Backups that I perform.

Every Monday I have a FULL backup which runs at 21:00 Hours.

Tuesday -> Sunday (Sunday Included) I have a differential backup which runs at the same time (21:00 hours).

However, yesterday the backup up, backed up 2 GB of data, but today it only backed up a maximum if 500 MB. Could somebody tell me why this is happening because I thought Differential Backups did not reset the Archive Bit on each file. This should mean that the 500 MB that it backed up today should get added onto the 2GB of data that was backed up yesterday.

With this happening, does it mean that some of the data is not getting backed up properly?? :S  Also, if I needed to restore the data, what should I do - Restore from the Last Full backup and then restore the data from the most recent differential back even though the most recent backup is smaller than the back up that was a day before that???

I am really very confused.

Some help would be appreciated greatly.

Regards,

Jonathan Worth

Network Manager

Hesa Limited

[Ken_Putnam]

You are correct.  A DIFF job should not reset the Archive Bit.  What you describe sounds like an INCR job

All I can suggest is recreating both the job and the associated selection list from scratch (don't try to edit the existing ones)

Do the FULL and the DIFF both use the same selection list?

[JWorth]

Hello,

Thanks for your quick I have just recreated the backup jobs. I now have two selection lists - one for the Tuesday Differential Overwrite and now I have another for the wed -> sun append job. And two seperate jobs to go with the defined selection list. I will see how I get on. If this does not solve my problem, what do you think is causing this problem.

To answer your question the, Full backup and the two differential backups all have their own selection lists.

Also differently from the last backup job I had (which is now delected) I have selected, "Append to media, terminate job is no media is appendable" instead of "append to media, overwrite media if no media is appendable". I don't know if this change anything, but it could be causing the problems.

Any more recommendations as to any other things that I could try would be appreciated greatly!!

Thanks and best regards,

Jonathan Worth

Network Manager

Hesa Limited