HP LTO Ultrium-2 drive compression

[Charles T Fischer]

I have a STK L20 tape lib. with an HP LTO2 drive. Software compression is off. I don't appear to be getting any hardware compression. Only getting 100gb per tape. Server is an Windows2000 box, driver is hplto.sys. Anybody have any ideas on how to enable hardware compression? I know on my HPUX boxes, it's handled via the driver. I have no idea here.

[Leif Halvarsson_2]

Hi,
Which backup software are you using, hardware compression on Windows is controlled by (and configured) the application.

Are you using LTO1 or LTO2 medias, as LTO2 medias has a native (uncompressed) capacity of 200GB it seems most likley that you use LTO1 media.

[Charles T Fischer]

well....they ordered me the wrong tapes, so i've got lt01 tapes (100/200)on an lto2 drive. So i figure I should end up somewhere between 100 and 200 gb depending on the data. Using Veritas Netbackup. But, I never use Netbackup's compression option, and I get compression on my dlt's everywhere else. So i'm guessing this must be a drive thing.

[Leif Halvarsson_2]

Hi,
Unfoutunatly I have no experience with Netbackup but I belive device configuration is rather similar to other backup program (I use DataProtector).

In DataProtector , hardware compression is controlled by the media agent, when configuring a (Windows) backup device you have an option to select hardware compression or not. With hardware compression enabled the device adress end with an "C" (e.g. scsi3:1:0:2C). With compression disabled, adress ends with "N".

Software compression is handled by the disk agent and is selected when configuring a backup job.

Is there any compression option in NetBackup when configuring a backup device and how does the adress for the device looks like ?

[Charles T Fischer]

That sounds like unix...i have a choice there...not on windows....cause, yaknow, windows likes to do the thinking for ya!

[Leif Halvarsson_2]

Hi,
No, not Unix. In Unix, hardware compression is controlled by the devicefile. Compressed or not compressed uses different devicefiles.

[Charles T Fischer]

True...god how i love my unix boxes...

Anyway...extra info, i have a similar setup at another facility, and that one is compressing just fine. Software setup is exactly the same. But on this other server (2003) when i look at the device in device manager, there is extra tabs that don't show on the 2000 server. The extra tabs state compression is on and enabled. I don't know if those extra tabs are a result of the different OS's or what, since they are both using the exact same driver. Are there any windows command line options to directly query the tape drive for information?

[Smucker]

Did you ever get this corrected. We appear to be having the same problem.

Lto2 stk Ultrium-2 hp-ux using veritas does not compress but the windows machines do.

[Charles T Fischer]

Nope....still no compression, unfortunatly, this library is in Mexico, so I have no "hands-on" for this. But, I do have the exact same setup in another office and they're getting great hardware level compression. With this second setup, I have another tab (in device manager for windows) that flat out shows hardware compression is enabled. I do not have that extra tab on my system in Mexico. The only difference is the OS, Mexico is 2000, the other is 2003. STK Mexico was called and they said there is no hardware compression for these drives, which in my opinion is a giant load of $$@#. At a standstill right now.

[Charles T Fischer]

i just re-read your post....is your L20 hooked up to an HPUX server? Is it an IBM drive?