Cisco ProtectLink Security

Forwarding Mail to Multiple Inbound Mail Transfer Agents (MTA) by Priority

Document ID: 109042

Updated: Dec 12, 2008


Q. How to forward mail to Multiple Inbound Mail Transfer Agents (MTA) by priority?


Putting a priority setting on your mail servers will make ProtectLink Gateway Email Protection follow a particular order when delivering inbound mail to your domain.

Step 1:
To do this, make a hostname that points to multiple mail exchange (MX) records.
Your DNS entries should be similar to this:

� IN MX 10
� IN MX 20
� IN MX 30
� IN A
� IN A
� IN A

Note: Contact your DNS technician if you need assistance.

Step 2:
We will then configure our Postfix servers to use:� smtp:

In this setup, our mail servers will try to deliver to If unsuccessful, we will try using mailserver2 and so on.

An email will be delivered only to the first server that accepts it and not to all servers.

This is useful when you have multiple locations, because there will still be other mail servers if one becomes unavailable.

Related Information

Updated: Dec 12, 2008
Document ID: 109042