Figure 6: Napt Example - Juniper JUNOSE 11.2.X IP SERVICES Configuration Manual

Copyright © 2010, Juniper Networks, Inc.

Figure 6: NAPT Example

The address pool consists of three addresses (the number of addresses is small, because
NAPT is used). Addresses matching the private address spaces of the corporate and
field subnetworks are translated to global addresses from the pool through NAPT.
To configure this example:
Enter the correct virtual router context.
1.
host1(config)#virtual-router blue
Mark the inside interfaces.
2.
a. Mark the field office:
host1:blue(config)#interface serial 2/1:1/1
host1:blue(config-interface)#ip nat inside
host1:blue(config-interface)#exit
b. Mark the two corporate T-3 links:
host1:blue(config)#interface serial 1/1
host1:blue(config-interface)#ip nat inside
host1:blue(config-interface)#exit
host1:blue(config)#interface serial 1/2
host1:blue(config-interface)#ip nat inside
host1:blue(config-interface)#exit
Mark the outside interface.
3.
host1:blue(config)#interface gigabitEthernet 3/0.1
host1:blue(config-interface)#ip nat outside
host1:blue(config-interface)#exit
Create a static nil-translation for the FTP server on the corporate network.
4.
host1:blue(config)#ip nat inside source static tcp 190.22.8.18 21 190.22.8.18 21
Create the address pool for dynamic translations.
5.
host1:blue(config)#ip nat pool corpxyz 192.32.6.4 192.32.6.7 prefix-length 24
Create the access list for addresses eligible for dynamic translation.
6.
host1:blue(config)#access-list justcorp permit 10.10.1.0 0.0.0.255
Chapter 2: Configuring NAT
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