Example For Configuring Twice Nat - Huawei S9700 Series Configuration Manual

S9700 Core Routing Switch
Configuration Guide - SPU
l

3.4.4 Example for Configuring Twice NAT

Networking Requirements
Basic NAT translates only the source or destination address of packets, whereas twice NAT
translates both the source and destination addresses. The twice NAT technology is used when
IP addresses of hosts on private and public networks overlap. As shown in
address of PC1 on the private network is the same as the IP address of host A on the public
network. If PC1 sends a packet to host A, the packet will be forwarded to PC2. The SPU supports
twice NAT and is configured with the mapping between the overlapping address pool and the
temporary address pool based on basic NAT. The overlapping IP address is translated to a unique
temporary address so that packets can be forwarded correctly.
The SPU is installed in slot 5 of the S9700.
Issue 01 (2012-03-15)
#
interface XGigabitEthernet0/0/1
eth-trunk 1
#
interface XGigabitEthernet0/0/2
eth-trunk 1
#
ip route-static vpn-instance vpn_b 0.0.0.0 0.0.0.0 Eth-Trunk 1.2 202.169.10.2
#
Return
Configuration file of the S9700
#
sysname S9700
#
vlan batch 101 to 103
#
interface Eth-Trunk1
port link-type trunk
port trunk allow-pass vlan 101 to 103
#
interface GigabitEthernet2/0/1
port link-type trunk
port trunk allow-pass vlan 101
#
interface GigabitEthernet2/0/2
port link-type trunk
port trunk allow-pass vlan 102
#
interface GigabitEthernet2/0/3
port link-type trunk
port trunk allow-pass vlan 103
#
interface XGigabitEthernet5/0/0
eth-trunk 1
#
interface XGigabitEthernet5/0/1
eth-trunk 1
#
return
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
3 NAT Configuration
Figure 3-7, the IP
107