SCSI tape: device not configured problem

[Dan Nelson]

In the last episode (May 28), Doug Poland said:
> I've been using an HP HP35480A 1109 DAT tape in a -STABLE box for
> about a year and half with no problems.  Just the other day, I
> started seeing
> 
>   mt: /dev/nsa0: Device not configured
> 
> errors whenever I try to control the device.
> 
> Should I just MAKEDEV nsa0 to fix it?  Is it perhaps a hardware
> issue? Thanks for your assitance.

This could mean you don't have a tape in the drive.  There are a
limited number of error codes the kernel can return, and ENXIO is a
catch-all for "I know what you want but it's not there":

     6 ENXIO Device not configured.  Input or output on a special file
             referred to a device that did not exist, or made a request
             beyond the limits of the device.  This error may also
             occur when, for example, a tape drive is not online or no
             disk pack is loaded on a drive.

You can use rsa0.ctl to send commands to the tape drive when there is
no tape inserted (to set compression or density for the next tape, for
example, or to read the error status)

-- 
	Dan Nelson
	dnelson at allantgroup.com