Setting up SMTP?

[James Wilkinson]

Ow Mun Heng wrote:
> 
> May I ask, what do you use the MSA for? I believe it's only for a
> _local_ mail submission. But what is the difference then to just point
> the submission to port 25 default?
> 
> I can understand the usage of MSA is  only port 25 is closed and you're
> not running as a mail-hub from internet.

One reason (you've been given others) is that it makes it easier to
firewall the MSA.

It should be practical, if the mail server is only serving a local
network, to set up the mail server only to forward from local IP
addresses. But if you want another layer of security, you can have two
copies of your MTA running (with different config files): one as the
inbound server, which won't relay for *anyone*, and one as the MSA,
which listens on a port that's been firewalled off from the Internet.

Paranoid, yes. Computer security is like that: you're never sure if
you're being way too paranoid, or not paranoid enough. Until you get
compromised.

Hope this helps,

James.

-- 
E-mail address: james | The camel has a single hump;
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