TOPS-20 Telnet and Port Forwading issue
imp at bsdimp.com
Tue Dec 13 00:10:57 CST 2016
On Mon, Dec 12, 2016 at 11:04 AM, Seth Morabito
<lists+cctalk at loomcom.com> wrote:
> Hi folks,
> I don't know if this is the best place to ask this question, but I don't
> know of any better forums for PDP-10 discussion, so hopefully it's
> on-topic enough.
> I recently set up the KLH10 PDP-10 emulator on my network, running
> TOPS-20 7.1. It's on a box in my 192.168.1.0/24 network. TCP/IP works
> great, I can telnet to it from within my network without any issue.
> I also set up my firewall (a box running CentOS 7.1) to port forward
> from external TCP port 2320 to internal TCP port 23 on the KLH10 box.
> Interestingly, when I telnet from _outside_ the network to my firewall's
> port 2320, it works, but Telnet goes into line mode rather than
> character mode! I can fix it with telnet escape (^]) by setting
> character mode explicitly with "mode character", but that's kind of
> annoying to do each time I connect.
> It feels like Telnet is no longer doing line mode / character mode
> negotiation when I'm port forwarding. It's most mysterious.
> If you want to see for yourself, you can telnet to
> gatekeeper.retronet.net 2320, which is the KLH10 instance.
> Does this ring any bells for anyone?
I'm guessing that this is the classic "Many telnet clients default to
line mode for only for port 23." issue.
More information about the cctech