HP35480 hardware compression linux

G

Guest

Guest
Archived from groups: comp.sys.hp.hardware (More info?)

G'day,

I suspect that this old HP35480 tape drive is not backing up to
capacity. Possibly becuase hardware compression is turned on, and the
backup software i am using uses software compression (AMANDA)

I have looked over the mt(1) man page and tried the compression
commands which exited silently and nothing in the logs suggested that
compression has changed.

I have just found this excellent posting circa '94 which seems to
explain why the mt commands don't appear to work...

http://groups.google.com.au/groups?hl=en&lr=&ie=UTF-8&safe=off&selm=CL027o.7wo%40bri.hp.com

So my question is "How do i send a mode select command under linux?"

I realise that i could set/check the switches on the device, however,
i'd much rather be able to do this remotely and without interrupting
client workflow.

Thanks in advance,

ram.
 
G

Guest

Guest
Archived from groups: comp.sys.hp.hardware (More info?)

Ram <ramsmith@gmail.com> wrote:
> G'day,
>
> I suspect that this old HP35480 tape drive is not backing up to
> capacity. Possibly becuase hardware compression is turned on, and the
> backup software i am using uses software compression (AMANDA)
[deleted]

If this is your suspicion (sp?) (which is a sensible one, because
software and hardware compression often/nearly_always conflict) then why
don't you disbale the hardware compression on the drive itself? AFAIK,
on all DDS drives, especially the old ones, you can (enable/)disable
hardware compression by setting a switch (or jumper) on the drive
itself.