User's Manual

Configuring Network Address Translation
308625-14.00 Rev 00
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Configuring Dynamic Local Address Ranges
The local address range is a group of unregistered source addresses used for
address translations. When NAT software detects an outbound packet from an
address within a configured local address range, it maps the local address to a
global address, replaces the packet’s local address with the global address, and
sends the packet to its destination address in another network. When NAT
software detects an inbound packet for a destination address that falls within the
configured global address range, it replaces the packet’s global destination address
with the original local address and sends it to its destination on the local network.
Adding a Local Address Range
The local address range is specified as a base address and a prefix length (from 1
through 32 decimal). The prefix length determines the number of available local
addresses. For example, if the local address is 10.0.0.0 and its prefix length is 8
(255.0.0.0), then the address range you specify includes addresses 10.0.0.0
through 10.255.255.255. If the local address is 10.1.10.0 and its prefix length is 24
(255.255.255.0), then the address range you specify includes addresses 10.1.10.0
through 10.1.10.255.
Using the BCC
To configure a local address range, navigate to the global NAT prompt (for
example,
box; ip; nat
) and enter:
local-range
<address>
/
<mask>
address
is the base local address expressed in dotted-decimal notation.
mask is the prefix length associated with the IP address expressed in decimal.
For example, the following command sequence configures 10.1.10.0/24 as the
local address range and verifies the entry:
nat#
local-range 10.1.10.0/24
local-range/10.1.10.0/24#
info
start-address 10.1.10.0
prefix-length 24
n-to-1 0.0.0.0
type 1-to-1
state enabled