I am new to devfs - it came with the Gentoo distribution of Linux I am
now using. I have a Cybernetics 15 slot tape library with drive that
has worked successfully on other distros. I'm really confused with
devfs.
I spent yesterday reading docs and working with devfs to get the thing
working and kind of succeded - once. When I started the system I had no
/dev/st - just /dev/sg, sd, sr. Sometime during the afternoon I did an
ls /dev/st again and there was the st directory. Using mt I managed to
test communciations and could talk to the tape drive under /dev/st. How
or why the /dev/st suddenly appeared I have no idea.
I shutdown the system and when I rebooted - no /dev/st anymore! My
original kernel was built with SCSI support built in as I have an
entirely SCSI system and did not want to mess with initrd. I could not
get /dev/st to show up again.
At that point I decided to build st support as a module and autoload it.
Did that and there was /dev/st with my tape devices!
At this point I'm confused. My understanding of devfs is that upon
startup (Gentoo boots with devfs running) devfs will find the devices
and create the necessary directories under /dev/. The devices ARE in
/proc/scsi/scsi. I can see that the module loading will cause devfs to
see a device added and create the directories. But why didn't devfs see
the devices when st support was built into the kernel??
Do I have to manually edit /etc/devfsd.conf to tell it to find my tape
and autochanger? I thought that devfs would find them by itself.
I've read man pages, the FAQ at the devfs author's site and asked on the
Gentoo and other Linux newsgroups but am still confused. In fact the
deafing silence on the mailing lists and newsgroups shows me not many
people understand devfs or so it appears. Any help in unconfusing me
would be appreciated.
Thank you.
--
Brett I. Holcomb
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