Problems using Windows Backup with a DLT1 unit

[Stuart Mackie [MCP, MSP]]

Hi. I am currently trying to take a 50GB Backup on Windows 2000 Server with
an HP Surestore DLT1. The unit and tapes are 40/80GB and when configuring
the backup I have selected Enable Hardware Compression. The backup always
over runs the one tape and requests a second which suggests it isn't using
compression.

Is it possible to get the Backup & Restore software in Win2k Server to use
Compression ?

Can anyone recommend any other better 3rd party software ?

 

[Pegasus \(MVP\)]

What exactly does your command line look like?

(e.g. ntbackup.exe /SomeSwitches)

 

[Stuart Mackie [MCP, MSP]]

I actually did it through the interface I'm happy to do it through the
command line if will actually work or if there are any advantages.

--
Thanks,
Stuart. MCP, MSP.
www.stu.uk.com

 

[Enkidu]

Hi. I am currently trying to take a 50GB Backup on Windows 2000 Server with
an HP Surestore DLT1. The unit and tapes are 40/80GB and when configuring
the backup I have selected Enable Hardware Compression. The backup always
over runs the one tape and requests a second which suggests it isn't using
compression.

Is it possible to get the Backup & Restore software in Win2k Server to use
Compression ?

Can anyone recommend any other better 3rd party software ?

Hi Stuart,

Having been through this myself, I sympathise. The reason for the
problem, I believe, is that the 2 x compression that the tape makers
claim depends very strongly on the compressibility of the data. If you
were able to get 50% compression in any real world situation, I'd be
very surprised. However, having said that if the 50GB had fitted onto
a 40GB tape, that would give you 25% compression and my experience it
should fit. But only just. It would leave virtually no room for
expansion. Maybe you data is not particularly compressible. In
addition, some tapes will have bad chunks and take even less.

I don't know how tape manufacturers can legitimately sell tapes as
40/80GB when you can usually get nowhere near the advertised 2 x
compression.

Cheers,

Cliff

 

[Stuart Mackie [MCP, MSP]]

Hi, thanks for your reply. I thought this might be the case. I checked and
the amount of data I was trying to fit onto the 40/80 tape was in fact
39.6GB. Some of the data was already compressed e.g. zipped but most of it
wasn't. I'm going to follow it up with HP and see what they say but it
looks as though it just isn't possible to fit it onto the tape which is
dissappointing.

I was hoping someone was going to tell me I was doing something wrong hehe

 

[Pegasus \(MVP\)]

Even if you did it through the interface, there is still a command line
behind it. Just examine the properties of the scheduled job it created,
by launching the GUI of the Task Scheduler.