L2NAT

ciscoenginner79 · ‎01-29-2021

HI Cisco Team.

I have an issue with l2NAT.

There are two machines with a plc that need to communicate see Network Topology below.
Both machines use NAT see NAT tables below.
We can ping and connect to the PLC from outside from an address to an address in production network 172.17.81.0/24.
We want to communicate from one PLC to the other PLC through local address 192.168.1.0
E.g. PLC 1 (192.168.1.4) wants to communicate with PLC 2 (192.168.1.4).
But we cannot get it to work

NAT tables:

Machine 1 #sh l2nat inst

l2nat instance MachineNAT

permit in : multicast

fixup : all

inside from host 192.168.1.4 to 172.17.81.204

outside from host 172.17.81.120 to 192.168.1.231

outside from host 172.17.81.1 to 192.168.1.1 gateway

Machine 2#do sh l2nat inst

l2nat instance MachineNAT

permit in : multicast

fixup : all

inside from host 192.168.1.4 to 172.17.81.120

outside from host 172.17.81.204 to 192.168.1.230

outside from host 172.17.81.1 to 192.168.1.1 gateway

Do You have any idea.

Regards

pieterh · ‎01-29-2021

as the NAT occurs in the Stratics switch, it would be better to ask this in a Stratix forum

on the outside network only 172.17.81.0/24 is used, this part of the network has no knowledge of the 192.168.1.0/24 addresses
take a look at the example in this Cisco L2NAT document, maybe this helps
*** sorry previus text here was wrong ***

maybe you need to apply the NAT config to the outgoing interface

Interface gig 1/1
 switchport access vlan 10
 l2nat instance10

ciscoenginner79 · ‎03-18-2021

Hi sorry for delay respond. The configuration seems OK. The problem may exist on PLC. The customer didn't replay back.