On Wed, 27 Jan 2010, Alan McKay wrote:
you need an MX for the domains you use in the envelope sender and
From/reply-To headers, not for a "box". The MX says which server to send
this or that mail to.
So let's assume I have mail.example.com as my Kerio server, at IP
10.11.12.13, and relay.example.com as my new Postfix server, at
10.11.15.16.
I currently have an MX for Kerio and it points at mail.example.com
Do I need one as well to point at relay.example.com? And if so, how
would I weight it?
I think you are still not getting what an MX does. An MX points the
right-hand side (domain) of an e-mail address at a machine that receives
mail for that domain.
You refer above to having an MX for Kerio pointing at mail.example.com but
that is not correct as Kerio is not a domain.
You should have an MX for each e-mail domain (right-hand side) pointing to
the server(s) that receive mail for it. If your Kerio server, which you
are calling mail.example.com is receiving mail for example.com, then you
need an MX for example.com (the e-mail domain) pointing at
mail.example.com (the machine). If some mail could potentially be sent to
u...@mail.example.com, then you also should have an MX pointing
mail.example.com (the e-mail domain) at mail.example.com (the machine).
As for relay.example.com, will the machine with that name receive mail? If
no, then no MX should point to it. On the flip side, is relay.example.com
a valid RHS of an e-mail address? If yes, then there should be an MX
pointing mail to whatever box will receive that mail (which may or may not
be the machine called relay.example.com - that's for you to decided and
configure).
-- Larry Stone
lston...@stonejongleux.com
