Setting Compression on 20/40gb DLT Drive

[Eric Coraccio]

I was wondering what you actually have to do to get this drive to use compression so I can try and fit up to 40gig on one tape. I am using DLT IV tapes. Is this something that needs to be done on the machine itself or is it something that needs to be done using software?

I am using Windows XP and the basic backup program that came with it.
Any help would be greatly appreciated.

Thanks.

[Munir_1]

I would recommend that you Run L&TT Diagnostic tool and Flash the firmware with new Firmware, even if you already have the latest firmware
then run the compression test.
http://h20000.www2.hp.com/bizsupport/TechSupport/SoftwareDescription.jsp?locale=en_US〈=English+%28US%29&pnameOID=12255&prodSeriesId=63896&prodTypeId=12169&basePartNum=COL1977&locBasepartNum=co-16463-1&os=Microsoft+Windows+XP&tech=Diagnostic

The other thing I would suggest is to try another software 3rd part software. To see if you would still get the same issue or not
It looks like the windows backup is disabling compression.

Munir!

[Eric Coraccio]

Thanks. I will try that. Do you know where I might be able to download the Firmware for this drive? I can't seem to find it on the link anywhere.

Also any recommended third party software for backups with compression?

[CA713937]

> It looks like the windows backup is disabling compression.

I think that's a common misconception.

Native windows backup (2k & XP) appears to disable compression AFTER the backup is complete. If you select the 'use hardware compression' option, it does enable the drive's data compression.

If you want to verify that the drive used compression, do the following:

1) Install HP LTT 3.4 (www.hp.com/support/tapetools)
2) Power cycle the drive
3) Load a tape and run the backup
4) Don't unload the tape
5) Run LTT and generate a support ticket
6) Look at the device analysis section. It will list the compression results.
7) (FYI for DDS drives, there is a data compression log section under the device details).

[Munir_1]

Firmware:
http://h20000.www2.hp.com/bizsupport/TechSupport/SoftwareDescription.jsp?locale=en_US〈=English+%28US%29&pnameOID=12255&prodSeriesId=63896&prodTypeId=12169&basePartNum=co563&locBasepartNum=co563en&os=Microsoft+Windows+2000&tech=Firmware

on L&TT go to firmware, then select local firmware file tap, the click on get firmware from web

[CA713937]

> Also any recommended third party software for backups with compression?

The native windows backup in 2k and XP is actually a version of Veritas backup. It does utilize hardware compression (as does virtually every other backup app).

LTT will automatically identify the correct firmware file for your drive using the "Get files from web" mentioned earlier.

[Eric Coraccio]

Ok great I appreciate the help. I just loaded the new firmware and will do a test backup and see if the compression worked. One other question. On the left hand side of the drive there are 4 sets of numbers then the word "compress" and the words "density override" what should be selected here??

Thanks again.

[CA713937]

> One other question. On the left hand side of the drive there are 4 sets of numbers then the word "compress" and the words "density override" what should be selected here??

Leave them alone. They are when you want to force the drive to a lower density and/or disable compression. The default is 20/40 GB with compression on.

Here's the manual:
http://h200005.www2.hp.com/bc/docs/support/SupportManual/lpg29237/lpg29237.pdf

[Eric Coraccio]

Ok thanks i have not touched it. It is on 20.0 and Compress there is no 20/40??

I am doing a test backup now and I will see if it does more than 20gig.

Thanks

[Munir_1]

Did you run the Compression test in L&TT?
What result did it give you?
Also make sure you are not Compressing Compressed data, because you will not get more than 20gb if data you are compressing are compressed already.
â Can not compress compressed data, data will get larger from all the over headâ
i.e. JPG files, Wav files e

[Eric Coraccio]

No I forgot to do that. Where is it anyway? i don't remember seeing it?

[Munir_1]

Select Test in L&TT, then Change Test Group: to Compression test, then start test
after you select the device

Munir!

[Eric Coraccio]

I had no idea that the compression hinders upon the type of files. Because i am making up mpeg2 files and ac3 and wav files of projects i am working on. So will the compression not work then?

[Mohammed Ali_2]

Eric,

Munir is right. On hp.com search this document lpg50244

Good luck and Happy Holidays

[Munir_1]

Take a look :
http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?objectID=lpg50244

only solution is to accept that the data cannot be compressed and use the required amount of media to store the data required.