Re: HP M8505 LTO3 FC Tape is compressed mode (655 Views)
Reply
Occasional Advisor
barkath
Posts: 16
Registered: ‎01-11-2007
Message 1 of 4 (689 Views)
Accepted Solution

HP M8505 LTO3 FC Tape is compressed mode

Hi all,

 

We have HP M8505 LTO3 FC tape drive connected H-Series system. We configured in SCF in compression mode and tape catridges used is 800GB LTO3 Tapes. Now the problem is , when we take backup of 1TB its using 3 800 GB LTO3 Tapes that means its not taking the backup in compressed mode.

 

so how to take backup in compressed mode.

 

Thanks in Advance.

Please use plain text.
Honored Contributor
Matti_Kurkela
Posts: 6,271
Registered: ‎12-02-2001
Message 2 of 4 (683 Views)

Re: HP M8505 LTO3 FC Tape is compressed mode

The "native" (uncompressed) capacity of a LTO3 is 400 GB, not 800 GB.

 

http://en.wikipedia.org/wiki/Linear_Tape-Open

 

If the data in your 1TB backup is already compressed or not compressible by nature (e.g. encrypted), the expected 2:1 compression ratio may not be realized.

MK
Please use plain text.
Occasional Advisor
barkath
Posts: 16
Registered: ‎01-11-2007
Message 3 of 4 (655 Views)

Re: HP M8505 LTO3 FC Tape is compressed mode

MK,

 

You are correct LTO3 native capacity is 400 GB.

 

But How to ensure that backup is taken im compressed mode?
How to check whether the HP M8505 tape drive is supporting compression mode?

 

Thanks,
Venkatesan.

Please use plain text.
Acclaimed Contributor
Dennis Handly
Posts: 24,854
Registered: ‎03-06-2006
Message 4 of 4 (652 Views)

Re: HP M8505 LTO3 FC Tape is compressed mode

>How to ensure that backup is taken in compressed mode?

 

Even if in compressed mode, some types of data can't be compressed, so you'll get only 400 GB.

Please use plain text.
The opinions expressed above are the personal opinions of the authors, not of HP. By using this site, you accept the Terms of Use and Rules of Participation