OK, one more question about sending email TO an old VAX

Peter Coghlan cctalk at beyondthepale.ie
Tue Feb 23 13:06:55 CST 2016

> Assuming I want to send an email message to an older VAX server (Process
> Software MultiNet V4.1 Rev A, MicroVAX 3100, VAX/VMS V5.5-2 ) that requires
> one to format their OUTBOUND emails like this:
> To: SMTP%"bill at myemail.net"
> How does one send mail INBOUND to this kind of VAX mail from a modern email
> like gmail?  Is it possible to format the header somehow to get the message
> through? You can't simply send a message to
> system at microvax3100.vintagecomputer.net
> how would I format the email address?  I could write a PHP program to
> format the header "wrong" for normal purposes but "right" for the VAX
> inbound I suppose.  Any tips that don't involve creating a gateway nor
> changing the target VAX itself?

Assuming they are configured correctly, VMS and Multinet are enough to make
your MicroVAX 3100 behave like any other SMTP mail server.  What you are
missing is a way of telling gmail (or wherever else you want to send the
mails from) how to route the mails to your MicroVAX 3100.

To do this, you need an "MX" record or "A" record in the DNS that specifies
the domain name and ip address of your MicroVAX 3100.  When this is put in the
DNS, any SMTP based mail server can look it up and find out where to send mail
for your domain to.  For example, something like this in the DNS zone file for

microvax3100 in mx 10 microvax3100
microvax3100 in a a.b.c.d

where a.b.c.d is the ip address the MicroVAX 3100 is configured with. (If the
machine lives behind a firewall, the ip address should be an external ip
address of the firewall and a suitable rule on the firewall should direct tcp
port 25 traffic to the internal ip address of the MicroVAX 3100.)

As I mentioned it before, I wouldn't do it this way because spammers will find
it and abuse it.  A better way would be to configure a more capable mail server
(such as the mail server that already handles mail for vintagecomputer.net) to
accept mail for microvax3100.vintagecomputer.net and forward it to the ip
address of the MicroVAX 3100.  The DNS entries would then point to this extra
mail server instead of directly to the MicroVAX itself.

To test that everying is configured correctly on the MicroVAX, you can telnet
to port 25 on the MicroVAX from itself or some other machine on the same
network and manually type in an SMTP mail, something like this:

telnet a.b.c.d /port=25 (from VMS)
telnet a.b.c.d 25       (from unix or Windows)

When you get the SMTP banner, enter this:

HELO domain
MAIL FROM:<postmaster at somewhere.com>
RCPT TO:<system at microvax3100.vintagecomputer.net>
From: postmaster at somewhere.com
To:   system at microvax3100.vintagecomputer.net

Test message

(The second last line is a period on it's own with no spaces.)

The Multinet telnet client will allow you to correct mistakes using DELETE but
many other telnet clients will mess up if you don't get everything exactly
right first time, so type carefully.

Then log in to SYSTEM and check for mail.

Peter Coghlan.

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