Compression problem

[Anthony_Lamb]

Hi
We have a customer with a Windows 2003 SBS server which is running Backup Exec V10.0 Build 5.484.

Up until the 2/11/2006 this worked without any problems backing up 31 GB of Data to a DDS4 tape drive, Now I am unable to back up any more then 23 GB of data without it failing.

I have brought a tape to my office and backed up 27GB on to it with no issues but on site it won't do it. The systme is an IBM server and I have spoken to their support who tell me it is not a problem with the tape drive.

I have tried getting the newest Veritas drivers but because my system is build 5484 and not higher I can't do that either.

Please can someone help

[Keith_Langmead]

Have you checked how much data the backup is trying to backup from the server? Eg has the amount of data increased recently?

It could be that someone or something has saved a load of data to the server which is not as compressible as that which was there already, and if that data gets backed up early on in the backup job then that could explain why the job is running out of space earlier in the job.

It is suprising that you're seeing such a large drop so quickly, but since you've confirmed that the tape works, that only really leaves the type of data that you're trying to compress for backup, or the possibility of a fault on the tape drive, though that should show up if you check for hardware errors in the media reports.

[Anthony_Lamb]

Hi

The data being backed up is bascially made up of Exchange data and word excel files with some Informix database files.

This has not altered at much in the last few weeks so the sudden drop is unexplained from the data point of view, I tried contacting the drive manufacturer and was soundly assured it was not their problem.

Any way I can improve this.

Anthony

[Asma_Tamboli]

Hello,

Have you already tried running a backup with software compression enabled so as to isolate the issue? You could also run a backup with ntbackup to compare the compression rates.

Also, please check out the following documents:

Backups fail to get double the amount of the native capacity recorded to a media, even when hardware compression is being utilized.
http://support.veritas.com/docs/199542

How to confirm that the data is being properly written to the tape media
http://support.veritas.com/docs/246958

[Anthony_Lamb]

Hi

I have tried running the backup with Software compression and it works every time so I changed the tape drive for another new one and it still will not back up the full amount of data.

With software compression I am currently backing up around 30Gb of data but with hardware compression I can only back up 22Gb.

Any ideas?

Regards

Anthony