tape compression

[Lonni J Friedman]

On Fri, Feb 29, 2008 at 4:41 AM, vu pham <vu at sivell.com> wrote:
> C M Reinehr wrote:
>  [...]
>  >> Do I have to run any extra command to force the tape drive to use
>  >> compression mode ? I already tried "mt -f /dev/st0 compression 1" but it
>  >> does not help.
>  >>
>
>  > What Bill says is very true, but here are some utilities that can be very
>  > helpful in figuring out what's going on. The tapeinfo command which comes in
>  > the mtx package can tell you explicitly if your hardware data compression is
>  > turned on or off. Check out, also, the scsitape command from the same
>  > package. Finally, there is the sg3_utils package which contains a number of
>  > useful SCSI utilities.
>  >
>  > Here's what the output of the tapeinfo command looks like on my system with a
>  > Tandberg LTO2 tapedrive:
>  >
>  [...]
>  > By the way, the command that I use to turn compression on & off is:
>  > mt -f /dev/nst0 defcompression 1
>  >
>  > Another thing is that with some tape drives (or so I've read) is that the
>  > compression & defcompression commands do not work. You have to set the
>  > density code.
>
>  CM, thanks for your advice.
>  I just installed the package mtx, but it complains that there is no sg
>  devices on my server. This server is a RH9. Can I make it see the tape
>  drive as sg device ?

RH9???  Jebus, that's like 6 year old software.


-- 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
L. Friedman                                    netllama at gmail.com
LlamaLand                       https://netllama.linux-sxs.org