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Re: HP M8505 LTO3 FC Tape is compressed mode

 
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barkath
Occasional Advisor

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.

3 REPLIES 3
Matti_Kurkela
Honored Contributor

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
barkath
Occasional Advisor

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.

Dennis Handly
Acclaimed Contributor
Solution

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.