Configuring Dynamic Nat Or Pat - Cisco PIX 500 Series Configuration Manual

Chapter 17 Configuring NAT

Configuring Dynamic NAT or PAT

This section describes how to configure dynamic NAT or dynamic PAT. The configuration for dynamic
NAT and PAT are almost identical; for NAT you specify a range of mapped addresses, and for PAT you
specify a single address.
Figure 17-20
and responding traffic is allowed back. The mapped address is dynamically assigned from a pool defined
by the global command.
Figure 17-20
10.1.1.1
10.1.1.2
Figure 17-21
responding traffic is allowed back. The mapped address defined by the global command is the same for
each translation, but the port is dynamically assigned.
Figure 17-21
10.1.1.1:1025
10.1.1.1:1026
10.1.1.2:1025
For more information about dynamic NAT, see the
information about PAT, see the
If you change the NAT configuration, and you do not want to wait for existing translations to time out
Note
before the new NAT information is used, you can clear the translation table using the clear xlate
command. However, clearing the translation table disconnects all current connections that use
translations.
To configure dynamic NAT or PAT, perform the following steps:
To identify the real addresses that you want to translate, enter one of the following commands:
Step 1
OL-12172-03
shows a typical dynamic NAT scenario. Only translated hosts can create a NAT session,
Dynamic NAT
Security
Appliance
209.165.201.1
209.165.201.2
Inside Outside
shows a typical dynamic PAT scenario. Only translated hosts can create a NAT session, and
Dynamic PAT
Security
Appliance
209.165.201.1:2020
209.165.201.1:2021
209.165.201.1:2022
Inside Outside
"PAT" section on page
"Dynamic NAT" section on page
17-8.
Cisco Security Appliance Command Line Configuration Guide
Using Dynamic NAT and PAT
17-6. For more
17-23