[CentOS] Mailers and records MX

[Les Mikesell]

On Tue, 2006-06-20 at 14:19 -0400, John Hinton wrote:
> >
> > Every seems to be fine, but I'm constantly receiving messages in my 3 MX
> > servers, even if mail.example.com (the less MX record) is available
> > waiting for connections from outside... Why if my less mx record server
> > is available the others servers are constantly receiving messages for my
> > domain?
> >
> >   
> There is a sendmail milter available for dealing with this. Basically, 
> it can tell the backup mailservers to look for the primary before 
> receiving mail. This is pretty much a must if you're going to do any 
> volume of reliable email service. It also can look ahead for a real user 
> before receiving mail on a backup system. The milter is called milter-ahead.
> 
> http://www.milter.info/sendmail/milter-ahead/
> 
> It does cost a bit... for commercial use.. or is free for individual use.

If you mean to check for a valid smtp recipient on a different machine
before accepting for forwarding, it is relatively easy to do that
with MimeDefang too - along with about any other virus or spam
checks you'd like: http://www.mimedefang.org/.

-- 
  Les Mikesell
    lesmikesell at gmail.com