[Simh] VAX DZ terminal controller unit?

[David Holland]

If all you're wanting to do is simply telnet into the VAX...

Assuming a recent Linux kernel

Bridge devices, and veth type devices will work wonders to get the VAX on
the LAN.

See:

http://comments.gmane.org/gmane.comp.emulators.simh/420  (or search the
archives)

As a good starting point....  Obviously, I've used them at one point..

David

On Thu, May 19, 2011 at 7:17 PM, Gary Lee Phillips <tivo.overo at gmail.com>wrote:

> On Thu, May 19, 2011 at 12:03 PM, Jason Stevens <neozeed at gmail.com> wrote:
> > I'd try the 'modem' setup for the DZ ... I recall something similar
> > with Unix/32v
> >
> > set dz lines=16
> > att dz -m 2311
> >
>
> Well, that sounded promising, but as far as I can tell, it made no
> difference at all.
>
> After a telnet session to the DZ port 8501, no matter how it
> terminates, the unit remains locked up for several minutes and cannot
> connect to the VAX emulation again. Eventually a security error is
> reported to the OPA0 terminal, saying that no input could be obtained
> from TTA0 and the connection has timed out. Then it is possible once
> again to connect through port 8501 for another session.
>
> Sessions work fine while they are connected. The issue is
> disconnecting and being able to reconnect. There appears to be some
> failure in handshake between the DZ emulation and the VAX driver, such
> that the closed telnet session, even if a hangup was sent, remains
> active (virtual DSR asserted, maybe?) for some length of time. This
> would be OK if the DZ emulation itself rotated through the available
> lines, sending the next connect request to line 2, and the next to
> line 3, and so forth, but it doesn't do that. As far as it is
> concerned, line 0 is now clear and the next SYNC results in a new
> connection to line 0. But the VAX driver isn't accepting that
> connection, or so it seems.
>
> The timeout seems to vary, anywhere from five minutes to fifteen or
> more. In one case the line was still tied up after sitting unused
> overnight.
>
> Just to clarify, as there seems to be some confusion, I want to use
> the DZ emulation to allow terminal sessions that originate on the same
> host box that runs the SIMH software to connect to the emulated VAX.
> This is not possible if the emulation and the host share the same NIC,
> but it can be done by going through the DZ, which provides a
> host-based port number. I am not trying to connect an actual VT
> terminal, and I don't see that the DZ emulation is really intended to
> do that. As for LAT, I found it cumbersome to use even when I had a
> real VAX and a real terminal server. It doesn't seem appropriate to
> this particular situation at all.
>
> --Gary
> _______________________________________________
> Simh mailing list
> Simh at trailing-edge.com
> http://mailman.trailing-edge.com/mailman/listinfo/simh
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.trailing-edge.com/pipermail/simh/attachments/20110519/62ec44cc/attachment.html>