> > The mail I was replying to here was about preventing unneeded CD changes
> > on a SCSI CD changer though, and I thought it might be nice to make such
> > code more general to prevent unneeded changes on any kind of changer.
>
> Yes, I've been thinking about doing this preventing somewhere at the block
> device level recently...
> Like this you'd say devices dev1, dev2, dev6, dev8, dev11 are related and
> should have these min and max times for accessing...
> Maybe a lot of effort could be saved by just using that stuff for read-only
> media (or are there any changers for writables? - I don't mean tapes, that's
> completely different thing).
Yes, HP makes several MO-changers, but these work _VERY_ different from a
CD changer. They have a lot of MO disks and several drives. Each drive has
either it's own ID or LUN (I don't know which, anybody ?) and the changing
mechanism has one too. In other words it works the same way a tape changer
does. I've also seen ad's for CD-Recordable changers that work much the
same way the MO changers do. I have no practical experience with either
device, my knowledge comes from paper and monitors.
It would be nicest if you could associate any block device with any other
block device, and be able to configure that at runtime. On the other hand,
autodetection of associated devices would also be nice. Maybe drivers
could register the association of devices with the kernel ?
--------------------------------------
Hugo Van den Berg - hbe@cypres.nl
Phone - +31 (0)30 - 60 25 400
Fax - +31 (0)30 - 60 50 799
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