Configuration Guide Configuring NAT
Configure the LAN interface to connect to the intranet as the NAT inside interface unless otherwise stated.
Configuring the NAT Outside Interface
Mandatory configuration.
Configure the WAN interface to connect to the extranet as the NAT outside interface unless otherwise stated.
Configuring Static NAT
Optional configuration.
Configure static NAT in global configuration mode when a small number of users in the intranet need to access the
extranet.
Configuring Dynamic NAT
Optional configuration.
Configure dynamic NAT in global configuration mode when a large number of users in the intranet need to access
the extranet.
Verification
N/A
Commands
Configuring the NAT Inside Interface and NAT Outside Interface
ip nat { inside | outside }
inside: inside interface
outside: outside interface
Interface configuration mode
NAT does not work on a data packet unless a route exists between the outside interface and the inside
interface and the data packet meets a certain rule. Therefore, at least one inside interface and one
outside interface need to be configured on the router.
Configuring Static NAT
ip nat inside source static local-address global-address [ permit-inside ] [ netmask mask ] [ match
interface ]
local-address: inside address
global-address: outside address
permit-inside: permits intranet users to access the local-ip host using global-ip.
netmask mask: network-segment-to-network-segment address
match interface: specifies the egress interface.
Global configuration mode