Compression on DDS tape.

[Durvesh Mendhekar]

Hi,

How can i achieve the compression by selecting which device file.

ioscan result:
hadmhp1:/home/datwor=> /usr/sbin/ioscan -funC tape
Class I H/W Path Driver S/W State H/W Type Description
=====================================================================
tape 0 0/0/1/0.2.0 stape CLAIMED DEVICE HP C1537A
/dev/rmt/0m /dev/rmt/0mnb /dev/rmt/c0t2d0BESTn /dev/rmt/c0t2d0DDSb
/dev/rmt/0mb /dev/rmt/c0t2d0BEST /dev/rmt/c0t2d0BESTnb /dev/rmt/c0t2d0DDSn
/dev/rmt/0mn /dev/rmt/c0t2d0BESTb /dev/rmt/c0t2d0DDS /dev/rmt/c0t2d0DDSnb

Regards,
Durvesh

[Raj D.]

Durvesh,

To achieve the data compression you have to use /dev/rmt/c0t2d0BESTn device file:

Defination of BEST:
BEST
Highest-capacity density or format will be used, including data compression, if the device supports compression.



n : (defination)
No rewind on close. Unless this mode is requested, the tape is automatically rewound upon close.

Hth.
Raj.

[Raj D.]

Also furthe reading: http://docs.hp.com/en/B2355-60130/mt.7.html

[Durvesh Mendhekar]

Hi,

Thanks

Found the solution

[Raj D.]

Durvesh Mendhekar,

BTW, you didn't yet assign any points in your recent or some earlier posts.


If you want to show appreciation when others
take time to reply to your questions, at a
minimum you should assign points.


Your profile says:
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[OldSchool]

actually, /dev/rmt/0m style devices *should* compress. if you look in the /dev/rmt directory they are probably links to the BEST definitions.

even if they aren't, running "lssf" on the device files will tell you which one does what.