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Cisco ASA 5500 Series Configuration Guide using ASDM
Chapter34 Configuring Twice NAT (ASA 8.3 and Later)
Licensing Requirements for Twice NAT
Twice NAT also lets you use service objects for static NAT-with-port-translation; network object NAT
only accepts inline definition.
For detailed information about the differences between twice NAT and network object NAT, see the
“How NAT is Implemented” section on page32-16.
Twice NAT rules are added to section 1 of the NAT rules table, or if specified, section 3. For more
information about NAT ordering, see the “NAT Rule Order” section on page32-20.
Licensing Requirements for Twice NATPrerequisites for Twice NAT
•For both the real and mapped addresses, configure network objects or network object groups.
Network object groups are particularly useful for creating a mapped address pool with discontinuous
IP address ranges or multiple hosts or subnets. To create a network object or group, see the
“Configuring Network Objects and Groups” section on page20-1.
•For static NAT-with-port-translation, configure TCP or UDP service objects. To create a service
object, see the “Configuring Service Objects and Service Groups” section on page20-5.
For specific guidelines for objects and groups, see the configuration section for the NAT type you want
to configure. See also the “Guidelines and Limitations” section.
Guidelines and Limitations
This section includes the guidelines and limitations for this feature.
Context Mode Guidelines
Supported in single and multiple context mode.
Firewall Mode Guidelines
•Supported in routed and transparent firewall mode.
•In transparent mode, you must specify the real and mapped interfaces; you cannot use --Any--.
•In transparent mode, you cannot configure interface PAT, because the transparent mode interfaces
do not have IP addresses. You also cannot use the management IP address as a mapped address.
IPv6 Guidelines
Does not support IPv6.
Model License Requirement
All models Base License.