Posted by under DECnet,OpenVMS,VAX on November 14 2018, 0 comments

After getting TCP/IP and a web server working on the simulated VAX, the next logical step would seem to be getting DECnet up and running, and then connecting to other machines.

Given the choice of HECnet or the Italian Hobbyist DECnet, I plumped for HECnet.

Then, of course I set about doing everything in completely the wrong order. Hopefully this is the right way to do things:

Firstly, contact Johnny Billquist of HECnet (his details are on the HECnet page) and agree on a NODE NAME and NUMBER, and a UDP port to use. I ended up with TARDIS, 1.250 and 6503.

Now use the DECnet address converter to find what MAC address you should be using for your VAX. My new MAC address is AA-00-04-00-FA-04.

Shut down your VAX and edit the vax.ini file, replacing the old MAC address with your new one.

Now, as for installing DECnet… Really it would have been easier if I’d installed it when setting up the machine. But as I’d still need to change the SCSNODE and SCSSYSTEMID (having gone with the defaults, possibly not. So:

$ set def sys$system
$ edit modparams.dat

You’ll need to change it to amend/add something along these lines (the actual values in italics WILL be different for you):


The run autogen and reboot…

$ set def sys$update
$ @autogen getdata shutdown nofeedback

And when the vax comes back up we’ll do some proper installing.

Meanwhile, on the machine that is going to act as a bridge (which can’t be the machine hosting the simulated VAX, and must have internet access) it is time to download and compile some software.

Grab the bridge program, untar it and compile it. The edit the config file according to what Johnny Billquist tells you to do (I had to change one line).

Meanwhile, back on the VAX: mount the install media filesystem, change into the DECnet directory and fire off the install.

$ set proc/priv=all
$ mount/over=id dua3:
$ set def dua3:[decnet_phase_iv_vax073.kit]
$ product install *

Now its time for some config…

$ set def sys$manager
$ @netconfig

Give it your DECnet Node Name and DECnet Address, and take the defaults for the rest.

Now, over on the bridge machine, start up the bridge program with the port number you’ve agreed on (in my case 6503):

$ sudo ./bridge 6503 &

Then start up DECnet on the vax:

$ @startnet

After a while, DECnet should come up. It still won’t know how to contact any other hosts on the DECnet, so you’d better tell it:

$ run sys$system:ncp
NCP>copy known nodes from 1037:: to both

And it all should work now. You should be able to SET HOST to your hearts content.

IMPORTANT NOTE: This stuff will only work if you’ve got in contact with Johnny Billquist and sorted out all the details for connecting your machine to his HECnet. Please change any parameters that look like they’ll mess up my connection, and let me know if I’ve made an obvious mistake somewhere.