Quantum DLT4000 on 4.5-R: "Device busy"

[Jerry McAllister]

Hi,

> Greetings,
> (Apologies in advance if this is not the correct list for this question)
> 
> I am attemping to get a new tape drive (Quantum DLT4000, external) working
> on my FreeBSD (4.5-R, i386) machine. The kernel detects the drive during
> boot:
> 
> ahc0: <Adaptec 2940 Ultra SCSI adapter> port 0xdc00-0xdcff mem
> 	0xe7003000-0xe7003fff irq 11 at device 13.0 on pci0
> aic7880: Ultra Wide Channel A, SCSI Id=7, 16/255 SCBs
> sa0 at ahc0 bus 0 target 4 lun 0
> sa0: <Quantum DLT4000 DA97> Removable Sequential Access SCSI-2 device
> sa0: 10.000MB/s transfers (10.000MHz, offset 15)
> 
> However, when trying to interact with the /dev/sa0 device via mt and tar
> commands, the device is reported to be busy:
> 
> [root at th]:/dev $ mt status
> mt: /dev/nsa0: Device busy
> ('mt offline' fails with the same message, as well)
> 
> I have tried resetting the drive, changing SCSI IDs, rebooting, reseating
> the tape cartridge, to no avail. The tape drive works under a
> Solaris/Sparc 8 machine, so I do not believe the drive or cable are at
> fault.
> 
> I am unfamiliar with tape drives in general under BSD. Am I doing
> something wrong?

First, I presume you have waited for the tape to quite cycling after
it is first inserted.  If not, then it actually is busy.

Second, we have seen this (or something that looks like it) with several 
machines that have DAT (DDS) drives.   Of about 65 supposedly identical
machines it happens on about 10 or 15 of them and we have not been able
to discover a reliable solution.  Sometimes a reboot with power-cycle (eg
turn the power off and pull all power cords for a couple of minutes to
let everything drain) clears it up, but most often not.   

So, if anyone has any good insight, I would also appreciate hearing
about it.

////jerry

> 
> -Luke
>