Juniper IP SERVICES - CONFIGURATION GUIDE V 11.1.X, Configuration Manual

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host1:blue(config)# ip route 192.32.6.0 255.255.255.192 null 0
NOTE: Null route applies to 192.32.6.0 and 192.32.6.1, which do not exist in the
address pool.
Twice NAT Example
Twice NAT is often useful when the inside network is using a nonprivate address
space (unregistered usage of global address space) and you want it to connect to the
public network. Inside local addresses need to be translated to legal global addresses.
Legal addresses from the outside that overlap those used on the inside network need
to be translated to unused and recognizable addresses in the inside network. Both
inside source and outside source translations must be configured on the NAT router.
Figure 8 on page 83 illustrates how the inside network is using the unregistered
global address space of 15.12.0.0/16. Outside hosts whose addresses overlap with
this subnetwork that want to access the inside network need their global addresses
translated.
Figure 8: Twice NAT Example
To configure this example:
1.
Enter the correct virtual router context.
host1(config)# virtual-router blue
2.
Mark the inside interface.
host1:blue(config)# interface fast-ethernet 6/1
host1:blue(config-interface)# ip nat inside
host1:blue(config-interface)# exit
3.
Mark the outside Interface.
host1:blue(config)# interface atm 3/0.20
host1:blue(config-interface)# ip nat outside
NAT Configuration Examples
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Chapter 2: Configuring NAT