Cisco Catalyst 6500 Series User Manual

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Catalyst 6500 Series Switch and Cisco 7600 Series Router Firewall Services Module Configuration Guide
OL-6392-01
Chapter 9 Configuring Network Address Translation
NAT Examples
Figure 9-19 shows a typical NAT exemption scenario.
Figure 9-20 NAT Exemption
Note If you change the NAT configuration, and you do not want to wait for existing translations to time out
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.
To configure NAT exemption, enter the following command:
FWSM/contexta(config)# FWSM/contexta(config)# nat ( local_interface ) 0 access-list acl_name
[outside] [norandomseq] [[tcp] tcp_max_conns [ emb_limit ]] [udp udp_max_conns ]
Create the ACL using the access-list command (see the “Adding an Extended Access Control List”
section on page 10-13). This ACL should include only permit access control entries (ACEs). Do not
specify the local and destination ports in the ACL; NAT exemption does not consider the ports.
See the “Configuring NAT or PAT” section on page 9-23 for information about the other options.
For example, to exempt an inside network when accessing any destination address, enter the following
command:
FWSM/contexta(config)# access-list EXEMPT permit ip 10.1.2.0 255.255.255.0 any
FWSM/contexta(config)# nat (inside) 0 access-list EXEMPT
To exempt an inside address when accessing two different destination addresses, enter the following
commands:
FWSM/contexta(config)# access-list NET1 permit ip 10.1.2.0 255.255.255.0 209.165.201.0
255.255.255.224
FWSM/contexta(config)# access-list NET1 permit ip 10.1.2.0 255.255.255.0 209.165.200.224
255.255.255.224
FWSM/contexta(config)# nat (inside) 0 access-list NET1
NAT Examples
The following sections show typical scenarios that use NAT solutions:
• Overlapping Networks, page 9-33
• Redirecting Ports, page 9-34
209.165.201.1 209.165.201.1
Inside
FWSM
Outside
209.165.201.2 209.165.201.2
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Cisco Catalyst 6500 Series Specifications

General

Brand	Cisco
Model	Catalyst 6500 Series
Category	Switch
Language	English