[Info-vax] VMS Emulation On Linux (was Re: CRTL and RMS vs SSIO)

[Lawrence D’Oliveiro]

On Saturday, October 16, 2021 at 12:36:21 PM UTC+13, I wrote:
>
> On Saturday, October 16, 2021 at 4:38:37 AM UTC+13, Arne Vajhøj wrote: 
>>
>> DECnet is a bit possessive with NIC's - first thing it does is to change 
>> the MAC address.
>>
> I know. It’s even more primitive than AppleTalk, it doesn’t have an ARP layer.
> So instead it has to compute the MAC address from the protocol address. 
> 
> But we can cope with that.

Turns out somebody else has been way ahead of us. Among the standard Debian packages is a DECnet implementation suite, apparently modelled on the Ultrix implementation <https://packages.debian.org/bullseye/libdnet>, <https://packages.debian.org/bullseye/dnet-progs>. Look at that, there is an equivalent to PHONE, there is a VMSmail-to-SMTP gateway, there is something called librms!

(How did I find it? I was just idly browsing the netlink(7) man page <https://manpages.debian.org/bullseye/manpages/netlink.7.en.html> -- as you do -- when I saw that the Linux kernel had provisions for handling DECnet routing messages. So I looked for userland packages that might use that, and there you are.)

Personally I would not allow DECnet anywhere near layer 2 on an actual physical NIC these days--I would cocoon it securely in a tunnel at layer 7. But I’m sure this implementation can cope with that ...