OT: Preferred MTA?

[Matt Hampton]

Pentland G. wrote:

>> Using DNS round-robin... :-(
> 
> Why? What for?
> 
> MX records (if you have more than at the same priority) will load balance anyway, I guess it is sort of a round robin.

Some servers always hit the first (ASCII wise) no matter what is returned.

It is better (as you have finally done Mr Pentland ;-) ) is to have a
single MX Hostname that resolves to multiple IP addresses.

> 
> You could deliberately have one at a lower priority, that would tend to attract spam and hence genuine mail would be on slightly less loaded servers.

To improve it:

MX	10	server1
MX	10	server2
MX	10	server3
MX	0	mail-server

where mail-server is DNS round robin for the IP addresses of server1-3.

This ensures that in the event of one of the servers being down and the
initial connection failing, there is a fall back which can be used.

Matt