Moxa V2401-LX [44/108] Nat network address translation

V2401/2402 Series Linux User’s Manual Managing Communications

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NAT (Network Address Translation)

The NAT (Network Address Translation) protocol translates IP addresses used on one network

into IP addresses used on a connecting network. One network is designated the inside network and

the other is the outside network. Typically, the V2401/2402-LX connects several devices on a

network and maps local inside network addresses to one or more global outside IP addresses, and

un-maps the global IP addresses on incoming packets back into local IP addresses.

ATTENTION

Click on the following links for more information about NAT.

http://www.netfilter.org/documentatio

n/HOWTO//packet-filtering-HOWTO.html

NAT Example

The IP address of all packets leaving LAN1 are changed to 192.168.3.127 (you will need to load

the module ipt_MASQUERADE):

#ehco 1 > /proc/sys/net/ipv4/ip_forward

#modprobe ipt_MASQUERADE

#iptables –t nat –A POSTROUTING –o eth0 –j MASQUERADE