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| 1.558 (RAPTOR) - OpenVMS Alpha: MONITOR SYSTEM |
One of my toys is RAPTOR, an emulated AlphaServer ES40 running OpenVMS Alpha 8.3 operating system. It connects to HECnet over DECnet Phase IV, and to the internet using Digital TCP/IP Services for OpenVMS. It runs an internet-facing web-server (OSU DECthreads HTTP Server for OpenVMS), effortlessly handling legitimate and spam traffic serving http://sanyal.duckdns.org.
Digital/Compaq/HP TCP/IP Services for OpenVMS Alpha 5.6 includes a SSH server allowing network access using SSL from SSH clients.
$ TCPIP SHOW VERSION
HP TCP/IP Services for OpenVMS Alpha Version V5.6
on an AlphaServer ES40 833 MHz running OpenVMS V8.3
Due to the age of TCP/IP Services for OpenVMS Alpha Version V5.6, modern implementations of SSH clients do not directly establish a secure communications channel with RAPTOR. Ubuntu 17 Linux, for example, provides the following contemporary SSH client:
someuser@moksha:~$ ssh -V
OpenSSH_7.5p1 Ubuntu-10ubuntu0.1, OpenSSL 1.0.2g 1 Mar 2016
and attempting to ssh directly to RAPTOR produces the following error:
someuser@moksha:~$ ssh vmsuser@10.42.2.12
Unable to negotiate with 10.42.2.12 port 22: no matching key exchange method found. Their offer: diffie-hellman-group1-sha1
Looking at the OpenSSH Legacy Options page, I created a ~/.ssh/config file with the following contents:
Host 10.42.2.12
KexAlgorithms +diffie-hellman-group1-sha1
I set the file permissions for ~/.ssh/config to owner-read/write only (not sure if it is needed), and tried again. But this time, a different error showed up:
someuser@moksha:~$ chmod 600 ~/.ssh/config
someuser@moksha:~$ ls -l ~/.ssh/config
-rw------- 1 someuser somegroup 88 Sep 26 02:17 /home/someuser/.ssh/config
someuser@moksha:~$ ssh vmsuser@10.42.2.12
Unable to negotiate with 10.42.2.12 port 22: no matching host key type found. Their offer: ssh-dss
Looking more at the OpenSSH Legacy Options page, I added another line to ~/.ssh/config file so that the ~/.ssh/config now has a total of three lines in it:
Host 10.42.2.12
KexAlgorithms +diffie-hellman-group1-sha1
HostKeyAlgorithms +ssh-dss
And presto, I am able to ssh from Ubuntu 17 into OpenVMS Alpha!
someuser@moksha:~$ ssh vmsuser@10.42.2.12
The authenticity of host '10.42.2.12 (10.42.2.12)' can't be established.
DSA key fingerprint is SHA256:somestring/somestring.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added '10.42.2.12' (DSA) to the list of known hosts.
vmsuser@10.42.2.12's password:
Welcome to OpenVMS (TM) Alpha Operating System, Version V8.3
System: RAPTOR, AlphaServer ES40 833 MHz
CPU 0 State: RUN CPUDB: 81C16000 Handle: * None *
Process: VMSUSER PID: 000000B9
Product: DECNET Node: RAPTOR Address(es): 1.558
Product: TCP/IP Node: raptor.sanyalnet.lan Address(es): 10.42.2.12
26-SEP-2018 02:07:25
$
$
$ lo
Connection to 10.42.2.12 closed.SEP-2018 02:09:35.51
someuser@moksha:~$
