With Policy NAT, the source address of interesting traffic can be changed to something else, especially in the case where there are networks that overlap.
In order to configure Policy NAT for VPN traffic, for example, to change the source address, refer to this configuration example. In this example, the internel network is 10.10.1.0/24.
- Create an access-list for Policy NAT with real source and a destination IP address.
access-list POLICYNAT extended permit ip 10.10.1.0 255.255.255.0 host 172.16.1.1
access-list POLICYNAT extended permit ip 10.10.1.0 255.255.255.0 188.8.131.52 255.255.255.0
- Create a static command that states that when source is 10.10.1.0 and destination is 172.16.1.1 or 184.108.40.206, change it to 172.16.5.0
static (inside,outside) 172.16.5.0 access-list POLICYNAT
- Create a crypto access-list with the source as the new IP address defined in Policy NAT, for example, 172.16.5.0.
access-list VPN extended permit ip 172.16.5.0 255.255.255.0 host 172.16.1.1
access-list VPN extended permit ip 172.16.5.0 255.255.255.0 220.127.116.11 255.255.255.0
- Apply the crypto access-list to crypto map.
crypto map VPN 10 match address VPN
VPN Tunnel End Points
Features & Tasks