Why can't I boot tape on 3B2/600?

[Kevin Darcy]

In article <498 at mtndew.Tustin.CA.US> friedl at mtndew.Tustin.CA.US (Steve Friedl) writes:
>Hi folks,
>
>     I have been having the damndest time getting a customer
>machine back up after a crash this weekend, and I am baffled as
>to why it is not cooperating with me.  They have a 3B2/600
>running SVR3.2, and they have a 60MB cartridge tape and a pair of
>internal hard drives (all of this is SCSI).
>
>     The root drive has a corrupted VTOC (probably my own damn
>fault), so I figured I would just boot from the OS tape and fix
>it right up.  Fat chance.
>
>     When I try to boot the machine, it does the SELF TEST and
>then hangs, presumably trying to filledt or run diagnostics off
>the hard disk.  If I hit the reset, I get the traditional SYSTEM
>FAILURE HAS OCCURRED, but the only boot device it allows me is
>FD5 -- no SCSI choice.  This is not a case of simply a missing
>name for an existing slot that would happen if filledt failed:
>the choices just aren't there.
>
>     When I try to boot the essential utilities floppy to run
>filledt, it fills a few slots and then powers down the machine:
>great!  I can't boot dgmon or /unix either.  None of this changes
>if I reset the NVRAM first.
>
>     What is happening here?  I understand that maybe it can't
>boot from the hard disk, but why in the world won't it let me
>boot from tape?  I really gotta get this machine working when I
>go out there on Monday morning at 6AM :-(

I'm not familiar with the "Essential Utilities Diskette" (I've always done 
such things from tape, or, when that fails, from the diskettes they distribute 
to data techs). I have, however, seen your power-off syndrome occur when techs 
try to run the wrong filledt/dgmon (the ones for smaller 3B2's). If you have a 
diskette that has utilities for ALL 3B2's on it, I think the ones for the 600 
and above are usually prefixed with "600", e.g. 600filledt. I can't vouch for 
the names completely (it's been a while since I've had to perform this 
particular exercise - thank the gods). In any case, they have different names.

You probably already know this, but you can get a list of files in the
floppy directory by entering a non-existent file name at the "Enter path 
name" prompt. See what's there. 

The fact that you don't see ANY choices for SCSI is disturbing. I assume
you've double-checked that the SCSI terminator is in firmly? If you were 
working on the inerds of the 3B2, you didn't happen to disconnect the cable 
that runs from the Host Adapter, by any chance?

By the way, if you manage to filledt and still can't boot off the internal tape
(assuming you get your SCSI choices back), try hooking up another tape drive 
externally and booting off that. I've found that marginal tape drives which 
work just fine for routine backup/restore stuff can nevertheless be lemons when
it comes to booting the OS from tape. Don't ask me why. Some sort of weird 
timing consideration, perhaps?
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