In spite of Bacula do not need different Media Types when using different LTO generations in tape libraries, I really think that it could be a best practice for working with LTO tapes to have the LTO tape generation specified in storage device definition. Just because of compatibility between tape drives and LTO generations: the hardware reads data from catridges in its own generation and at least two prior ones and writes in its own generation and to catridges that are in the immediately prior generation (using the immediately prior generation format). Suppose you have an LTO-3 drive working with LTO-3 catridges and you upgrade your hardware to an LTO-5 drive that will not write to your LTO-3 catridges because of compatibility. If you just specify "Media Type = LTO", Bacula will try to read and write to all the LTO-3 and LTO-5 catridges and this will no work. Is there another way of distinguishing different LTO catridge generations? Normally I have been using this way: having two storage device definitions for the same drive, each one working with an LTO catridge generation.
> Which is why I'll never understand the tape/disk dichotomy.
>
> (As an aside, bacula, specifically, seems to force you to use
different
> Media Type for each physical device so I don't get how it
would work
> with multiple drives in the same jukebox, either --
thankfully I don't
> need to.)
To be more precise, Bacula does not require you to use different
Media Types for different devices. It only does so for different
disk devices so that it can be sure where the Volume is actually
stored. For a compatible tape drives in an autochanger, there is
no need to have different Media Types. However, if you have
multiple separate libraries the Media Type must be different so that
Bacula is sure what library the Volume is in (it actually keeps a
device index, but this is often insufficient).
