NAT Rules

There are two types of NAT rules: static and dynamic. Static NAT rules provide a one-to-one translation of addresses. Dynamic NAT rules provide an N-to-M, typically many to one, translation of addresses.

NAT rules are specified by their type (STATIC or DYNAMIC), their source and translated source address, and their destination and translated destination address. Addresses in NAT rules use the same set of address objects used in other rules.

NAT rules are ordered. The first NAT rule that matches a packet takes effect, and no other NAT rules apply. Therefore, place specific NAT rules first, and broader NAT rules later.

Valid translations are:

• Source and Translated Source are the same, and Destination and Translated Destination are the same (no translation occurs).

• Source and Translated Source are the same, and Destination and Translated Destination are different.

• Source and Translated Source are different, and Destination and Translated Destination are the same.

You cannot translate both the source and destination addresses in any single packet with either a single translation or in a combination of translations. A nontranslating NAT rule may be placed ahead of more general NAT rules, to override part of the later, more general NAT rule.