HW compression problem with DPE

CarlLawton — Mon, 10 Sep 2007 05:46:29 GMT

Hi All,

Server is HP ML350 with internal DAT72 USB.
DPE is Single Server Edition 3.10-sp4 (build 25352). The tapes are HP's own DAT72

I'm trying to do a full backup of around 47GB every night with no media rotation. It is a "Run repeatedly" type schedule. The options are:

Backup Mode: Full
Auto Verify Mode: Quick Verify
Write Mode: Overwrite all media
Span mode: Restart File
Change mode: Force to append to end of media
Software Compression: None
Hardware Compression: Compressed

The Auto format mode is "Auto format all media".

I'm currently having to put in another tape to finish off the backup but need it on one tape.

In the logs i get:

-------------------------------------------------------------------------------
Media
-------------------------------------------------------------------------------

Home\Admin\Media:3
Completed: 21246 objects, 3.85 GB

Home\Admin\Media:11
Completed: 45125 objects, 41.19 GB

The media:11 above shows 41.19 Gb so some compression must be happening.

However if i run the LTT compression test i always get in excess of 2:1 compression ratio.

Any help of getting this on one tape much appreciated.

TIA
Benway

Re: HW compression problem with DPE

Lewis Finch — Mon, 10 Sep 2007 11:22:31 GMT

Hardware compression is enabled by default and that is what you are, and should be , using. here is a very good document explaining what kinds of files compress well and what kinds do not. It is likely you are backing up already compressed files and they cannot be compressed more.

http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?objectID=lpg50460

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HW compression problem with DPE

Re: HW compression problem with DPE