Bauer, Stefan (IZLBW Extern):
> Dear Developers/Users,
>
> We want to load balance mails from the intranet to the
> postfix-relayserver-farm for outgoing traffic. Can we abuse
> A-records to load-balance in the same way MX-records have been
> designed?
Yes, if the sender is Postfix. Postfix will randomly select from
equal-preference IP addresses and IP protocols. This is intentional,
so that mail does not get stuck when one path is broken.
Other MTAs may use a different approach, For example, they may try
only one IP address per MX record, or they may try IPv4 only after
they fail to deliver mail over IPv6.
Wietse
