Help sought on problem with uucp acucntrl

[Wayne Little]

In article <106 at umree.UUCP>, rwl at umree.UUCP (Wayne Little) writes:
> We are experiencing a side effect with the acucntrl part of uucp 4.3.
> The dial out part "turns off" the getty and works fine, but the getty does
> not get restarted on the line & I can't get it to come back (kill -HUP 1
> doesn't work, and the line in /etc/ttys is enabled).

The FIX involved wiring up leads 1-8 & 20 of the RS 232 cable to the modem.
[We didn't have any flat 25 wire cable, & I knew the others weren't used
much in the RS 232 protocol; we only had 2, 3 & 7 before - dumb, I know (now).]

A hypotheis of the problem, supplied by Dave Greunke -
{seismo,ihnp4,harpo}!uwvax!astroatc!vid, follows.
The key may be the cabling to your modem. We have a 25 conductor flat cable
going from our modems to the Able DH-11 multiplexers so all signals are
brought thru to the modems (We use Ventel 212+ rackmounts). I have poked
thru the acucntrl code a bit (I don't claim to understand it yet) and I know
that Sebok pokes into the kernel tty structures (via /dev/kmem) and fiddles
with the modem control bits of the the multiplexers. What may be happening
is acucntrl may drop DTR from the mux (to reset the modem) and then expects
the modem to respond (with what I'm not quite sure). If the modem doesn't
respond the mux may hang.

A side note is that other people have experienced the getty not being
put back on the line following the acucntrl poking, UNTIL someone dialed
in on the line, and then all was well.  This was not the case with ours.

Thanks also to Kurt Haserodt (ihnp4!wucs!kurt) who also suggested running
a cable with the DTR lead in it, and to David Herron (cbosgd!ukma!david)
for his reply.