== 2026-08-22 Monday ==

==== Using SSH to tunnel Telnet ====


After my last post about setting up a netbook, to use mostly
software and protocols that were available in 1993 (give or take),
I decided after all to install OpenSSH-Client

SSH didn't appear until 1995, and OpenSSH until 1999 and I
initially didn't want to use it....

But.....

I have ONE use-case in mind.

I /want/ to use only Telnet, FTP, Gopher for most of my network
"admin" around my LAN. That's fine when I'm at home. 

But I /would/ like to access the LAN from outside, from the wild
internet. In the past I've just opened a random port on my NAT
Router and forwarded it to an SSH port on an internal machine and
then I can SSH in from outside.

I briefly toyed with the idea of opening up another random port and
forwarding it to port 23 on an internal machine. Then I can telnet
in from outside.

I'd have Telnet access from the internet.

In the "good olde days" that would have been fine. But not
nowadays.

So, instead, I could just install SSH on the "1993 Netbook" and
continue as I've done for many years.... ssh'ing in from outside.

But I _want_ to use Telnet. 

Not for any practical reasons. 

Obviously SSH is /much/ more versatile than Telnet. You'd be mad to
choose Telnet over SSH.

And for the sake of argument, yes, let's assume I'm mad...

So I installed OpenSSH-Client on the netbook and I'm using it
purely to use a LocalForwarding to tunnel Telnet over the SSH
session...


	ssh -p XXXXX xxxxxx.xxxx.xxx -L 2023:localhost:23

once the SSH session is up I just switch to another VT (or t-mux
pane) and I can then connect via telnet to my internal machine

	telnet localhost 2023

Once inside via Telnet I can get on with pretending it's 1993...

It's daft, yes, to set up a connection, with a login, and then
ignore that shell, and then login again via Telnet.

But who cares...?