Won't Compress Data

[Intelligence]

I'm having problems compessing the backup data to fit on a tape, My tape drive lets me compress data and I was able to use the windows backup to perform that but I cant get Retrospect to compress the backup i have turne on both hardware compression and software compression, the tape drive i use is a Quantum SDLT 160GB -320GB, I'm using Retrospect 7.0 and the amount of data that needs to be backed up 200GB. Any ideas?

[nembot]

Hi,

 

Retrospect only performs a compression in software but as the hardware compression is most powerfull, the software compression is disable when the hardware compression is on. You'll never have 320GB data on a tape here.The compression rate depends on the type of data you're backing up;Check with your hardware manufacturer on how to increase the compression rate.

 

Thanks,

[compdoc]

The drive should have hardware compression, which is usually enabled by default. Some have jumpers to control it, however.

 

And it's independent of the backup program, so you dont need to enable any form of compression in the program. In fact, its best not to enable software compression for these drives - you just slow things down.

 

That said, what type of data is being backed up? If its video or music, or other files that contain compressed data, you just aren’t going to get them compressed any further, and you'll only get 160 gigs on the tape...

[michaeln]

Hi,

 

Another thing to note, Retrospect will not use hardware compression if the data set is encrypted because encrypted data compresses poorly.

 

If you have software compression enabled, Retrospect will compress the data and then encrypt it.