3b1's OBM hanging the line

[Donald Lashomb]

In article <1990Feb8.155753.3090 at chinet.chi.il.us> john at chinet.chi.il.us (John Mundt) writes:
>I have a 3b1 which suddenly gets tied up after I call *into* it from
>another machine.  When I log out with a ^D, the 3b1 does not disconnect
>but rather gives a "login" message.  However, it never accepts a
>login, always saying "login incorrect."  When I force a disconnect 
>from outside, the 3b1 will no longer answer the line.  The machine has
>been fine for two years before this, and even now, uucico can get in
>and out from the outside without tying up the line.
>
>Going to the machine shows no getty or login running on the phone
>port, even though /etc/inittab should respawn a getty.  Doing a
>"init q" will respawn the getty, but the modem still does not
>answer the phone.  
>
>The process table doesn't show any process, zombie or otherwise,
>that could be connected to the phone port.  phtoggle does not
>clear the problem.  Rebooting the machine is the only way to
>clear the problem.
>
>The hotline's suggestion is to reload UNIX.  Has anyone else had
>this problem and a solution for it?
>-- 
>---------------------
>John Mundt   Teachers' Aide, Inc.  P.O. Box 1666  Highland Park, IL
>john at admctr.chi.il.us *OR* fred at teacha.chi.il.us
>(312) 998-5007 (Day voice) || -432-8860 (Answer Mach) && -432-5386 Modem  


Yes, I am having a related problem with my 7300 since installing FixDisk2.
Here is what I recently posted:

	     ====================

Unix-pc group,     +----------- has happenned 8 or 9 times now!
                   v
I have experienced 2 lockups since installing FixDisk2 of a type that
has never happened to me before.  It seems that init sometimes fails to
respawn getty after I logout.

I am pointing my finger at FixDisk2 because:
	1. It never happened before to me.
	2. FixDisk2 included new versions of init and getty.
	3. There seems to be some mis-handling of wtmp/utmp,
	   exactly the area of concern that FixDisk2 addressed.

There is a remote chance that this could be a problem in wind.o, since
of course, init is supposed to respawn getty /dev/window.

----------------------

Here are the symptoms:

		Welcome to the Unix PC
		Please login: install
		Password:

		$ windy -b ksh			# I like having 2 shells

	[ do normal work everything seems ok ]

		$ <cntl-D>			# exit second shell
		$ <cntl-D>			# exit first (login) shell

	[ screen blanks - NO Welcome, NO Please login ]

	Point mouse at ph mngr window, click.  Call screen of install
	appears - appearently ph thinks install is still logged in.
	This might be trouble with wtmp/utmp files.  Get a shell so I
	can see what is going on :->

		# ps -e
		[ no getty on w1 ]
		# init q
		[ no difference ]
		# killall
		# sync
		# reboot

I don't think my playing around with having two shells going (windy -b ksh)
has anything to do with the problem.  I am careful to exit the second shell,
thereby closing its window, before I exit the first shell (logout).  I only
include it here for completeness of the discussion.

----------------------

If anyone has had a similar experience, before or after installing FixDisk2,
please post or email me what you know about it.

Thanks in advance,
-Don			donlash at uncle.UUCP

	     ====================

I still have not been able to find out what the problem is.  I was able to
confirm that getty is definately NOT being respawned by init.  There seems
to be some weird modification/access/stat-change times with utmp.  I tried
reloading the old version of init (keeping new versions of getty and login).
This seemed to work for 4-5 days, then Wham, the machine locked up twice.

The worse part of this problem is that it is so unpredicatable.  I have yet
to figure out just what circumstances it happens under.  I don't think I'm
doing anything other than what I always do and sometimes it happens, some-
times it doesn't (race condition, missed signal, phase of the moon?).

Currently, I'm running the old init, getty, and login, but the new 3.51m
kernel.  Haven't had any trouble so far, but then again it's only been half
a day.  I won't feel comfortable, until it's been at least a week with no
trouble (is that long enough to be sure?).

Oh yeah, I've double checked the sums of my fix disk with those posted on
the net, there ok.  I've even run memory and disk checks from the Diagnostic
Disk - everything checks out ok.

If anybody out there has any ideas as to what the problem is, *PLEASE*
let me know.  Thank you Lenny for your help so far.

-Don		donlash at uncle.UUCP