[TUHS] BSD 2.11 on PDP11/70 (emulated), connecting to it via a slip interface

[Folkert van Heusden via TUHS]

Hi,

As I mentioned a year ago I'm working on a pdp11/70 emulator. Just for 
fun, not serious like simh.

Currently it can run BSD 2.11 multiuser on an ESP32-S3 (altough booting 
takes almost 50 minutes on that platform).

It also runs on Linux etc. So I setup a BSD kernel with slip and dz11 
support to allow telnet over IP with slip. Unfortunately that hangs. I 
can ping, I can nmap the virtual PDP but telnet to the PDP just does 
SYN/SYNACK/ACK and then nothing. Any ideas why telnet would hang?

Pinging the pdp:

root at snsv:~# ping 192.168.1.2
PING 192.168.1.2 (192.168.1.2) 56(84) bytes of data.
64 bytes from 192.168.1.2: icmp_seq=1 ttl=255 time=77.5 ms
64 bytes from 192.168.1.2: icmp_seq=2 ttl=255 time=185 ms
64 bytes from 192.168.1.2: icmp_seq=3 ttl=255 time=90.2 ms
^C
--- 192.168.1.2 ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2004ms
rtt min/avg/max/mdev = 77.503/117.547/184.895/47.905 ms

nmap:

Nmap scan report for 192.168.1.2
Host is up (0.069s latency).
Not shown: 990 closed tcp ports (reset)
PORT    STATE SERVICE
1/tcp   open  tcpmux
7/tcp   open  echo
9/tcp   open  discard
21/tcp  open  ftp
23/tcp  open  telnet
79/tcp  open  finger
113/tcp open  ident
513/tcp open  login
514/tcp open  shell
515/tcp open  printer
Device type: general purpose
Running (JUST GUESSING): BSD 2.X (85%)
OS CPE: cpe:/o:bsd:bsd:2.11
Aggressive OS guesses: 2.11BSD (85%)
No exact OS matches for host (test conditions non-ideal).

OS detection performed. Please report any incorrect results at 
https://nmap.org/submit/ .
Nmap done: 1 IP address (1 host up) scanned in 27.90 seconds

telnet network trace:

10:39:41.390230 IP 192.168.1.1.55606 > 192.168.1.2.23: Flags [S], seq 
730571314, win 65535, options [mss 256,sackOK,TS val 1346414773 ecr 
0,nop,wscale 10], length 0
10:39:41.458696 IP 192.168.1.2.23 > 192.168.1.1.55606: Flags [S.], seq 
43457, ack 730571315, win 4096, options [mss 966], length 0
10:39:41.458753 IP 192.168.1.1.55606 > 192.168.1.2.23: Flags [.], ack 1, 
win 65535, length 0
10:39:41.459364 IP 192.168.1.1.55606 > 192.168.1.2.23: Flags [P.], seq 
1:31, ack 1, win 65535, length 30 [telnet DO ENCRYPT, WILL ENCRYPT, DO 
SUPPRESS GO AHEAD, WILL TERMINAL TYPE, WILL NAWS, WILL TSPEED, WILL 
LFLOW, WILL LINEMODE, WILL NEW-ENVIRON, DO STATUS]
10:39:42.035173 IP 192.168.1.1.55606 > 192.168.1.2.23: Flags [P.], seq 
1:31, ack 1, win 65535, length 30 [telnet DO ENCRYPT, WILL ENCRYPT, DO 
SUPPRESS GO AHEAD, WILL TERMINAL TYPE, WILL NAWS, WILL TSPEED, WILL 
LFLOW, WILL LINEMODE, WILL NEW-ENVIRON, DO STATUS]
10:39:43.123157 IP 192.168.1.1.55606 > 192.168.1.2.23: Flags [P.], seq 
1:31, ack 1, win 65535, length 30 [telnet DO ENCRYPT, WILL ENCRYPT, DO 
SUPPRESS GO AHEAD, WILL TERMINAL TYPE, WILL NAWS, WILL TSPEED, WILL 
LFLOW, WILL LINEMODE, WILL NEW-ENVIRON, DO STATUS]
...

regards

-- 
www.vanheusden.com [1]

Links:
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