9-26
Catalyst 6500 Series Switch and Cisco 7600 Series Router Firewall Services Module Configuration Guide
OL-6392-01
Chapter 9 Configuring Network Address Translation
Using Static NAT
Using Static NAT
This section tells how to configure a static translation.
Figure 9-16 shows a typical static NAT scenario. Both local and global traffic can originate connections,
and the global address is statically assigned.
Figure 9-16 Static NAT
You cannot use the same local or global address in multiple static statements between the same two
interfaces. Do not use an address that is also defined as a dynamic PAT address in a global statement.
For more information about static NAT, see the “Static NAT” section on page 9-5.
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 static NAT, enter one of the following commands.
• For policy static NAT, enter the following command:
FWSM/contexta(config)# static (
local_interface
,
global_interface
)
{
global_ip
| interface} access-list
acl_name
[dns] [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). The
source subnet mask used in the ACL is also used for the global addresses. You can also specify the
local and destination ports in the ACL using the eq operator. See the “Policy NAT” section on
page 9-8 for more information.
See the “Configuring NAT or PAT” section on page 9-23 for information about the other options.
• To configure regular static NAT, enter the following command:
FWSM/contexta(config)# static (
local_interface
,
global_interface
)
{
global_ip
| interface}
local_ip
[netmask
mask
] [dns] [norandomseq]
[[tcp]
tcp_max_conns
[
emb_limit
]] [udp
udp_max_conns
]
See the “Configuring NAT or PAT” section on page 9-23 for information about the options.
10.1.1.1 209.165.201.1
Inside
FWSM
Outside
10.1.1.2 209.165.201.2
114406