Tape Device file differences...

[Marco Greene (Home)]

..I am a little confused about tape devices in FreeBSD.

Under the /dev directory...I have the following tape devices:
# ls *sa*
ersa0           esa0.1          nrsa0.3         rsa0.0          sa0.1
ersa0.0         esa0.2          nsa0            rsa0.1          sa0.2
ersa0.1         esa0.3          nsa0.0          rsa0.2          sa0.3
ersa0.2         nrsa0           nsa0.1          rsa0.3          sa0.ctl
ersa0.3         nrsa0.0         nsa0.2          rsa0.ctl
esa0            nrsa0.1         nsa0.3          sa0
esa0.0          nrsa0.2         rsa0            sa0.0

I have figured out most of it by searching on the net...but any
clarification or pointers to documentation would be helpful.

This is what I have figured out so far (feel free to correct me if I am
wrong).
-e[r]sa0 = Eject
-n[r]sa0 = No Rewind
-[r]sa0 = Rewind
-The .ctl file should be used with the "mt" command.



This is what I still need explained:
-The difference between the /dev/*rsa0 devices and /dev/?sa0 devices?  i.e.
What is the "r" for?
-What is the .0, .1, .2 and .3?

Thanks,
Marco