Zhone 5100 Manuale Di Riferimento
Loopback interface commands
Vpacket 5100/6100 Series Reference Manual
91
In this example, the loopback interface IP address and subnet mask are now added to the IP
Interface table ( see Figure 3-1 on page 54).
Setting the loopback interface to be a NAT outside interface
Since the loopback IP address is a publicly visible IP address, it can be used as the NAT IP
address. This type of setup can be used in a network environment where the WAN IP address is a
part of the ISP’s private address space, and the ISP is trying to conserve IP addresses by allocating
just one IP address per customer connection.
The loopback interface IP address can be a NAT IP address; however, by default, the NAT IP
The loopback interface IP address can be a NAT IP address; however, by default, the NAT IP
address is the WAN IP address. You can set an outside NAT interface by issuing the set nat
outside_interface command.
Note. This command is used to select the IP address of either the WAN or the
loopback interface as the NAT IP address.
Vpacket recommends that the “outside_interface” be setup prior to modifying any other NAT
configuration, in order to avoid losing any configured but un-saved changes.
When this command is issued, all active data connections across the unit are dropped if NAT is
When this command is issued, all active data connections across the unit are dropped if NAT is
enabled because the NAT module does a soft reset. The 5100/6100 VDR unit does not reset, just
the NAT module.
Syntax: set nat outside_interface <wan | loopback>
Argument:
Syntax: set nat outside_interface <wan | loopback>
Argument:
wan |loopback
wan is used if the network setup is similar to Figure 3-4 on page 88
loopback is used if the network setup is similar to Figure 3-5 on page 89
Example:
In this example, the loopback interface is chosen as the NAT outside interface IP address.
In this example, the IP interface table lists the interface names, IP addesses, netmasks, and
In this example, the IP interface table lists the interface names, IP addesses, netmasks, and
whether the interface is primary (NATed) or secondary (Not NATed).
VPacket# set nat outside_interface loopback
Warning: All unsaved NAT configuration items and all active
data connections through NAT will be lost
Do you want to continue (y|n) [n]? y
VPacket#