[Info-vax] TCPIP tying up system

[Jan-Erik Soderholm]

On 2010-11-30 23:36, JF Mezei wrote:
> Jan-Erik Soderholm wrote:
>
>> Not that it matters much, but I have been configuring SMTP on a number
>> of TCPIP versions and never found RELAY as the default.
>
>
> NORELAY is the default. But this makes your SMTP server non functionial
> if it faces the internet. You need to enable RELAY, and add Relay-Zones:
> in the SMTP.CONFIG files to define which domains are considered local
> (aka: can receive emails form the outside workld)
>

I'm not following here...

What does "facing the internet" mean ? As far as TCPIP
Services in concerned, it doesn't see any difference between
any (local) TCPIP host and "the Internet". There is nothing
magic about "the Internet"...

The only reason to have RELAY is if your VMS server
actualy *will* be relaying SMTP traffic between different
(external) servers/hosts. As long as a local VMS user is
either the sender or receiver, there is no need for RELAY.

Note that, if you have some software localy on your VMS
server that actualy opens port 25 on "localhost" and writes
directly to the SMTP server (the recevier part), that is
also (as far as the SMTP server is concerned) beeing seen
as an external call. The NBL tool is one such tool.