Ignition access to subnetwork PLC

I have a networking maze that I am trying to navigate. I have Ignition communicating with a Rockwell PLC at 172.16.x.x. This PLC has a processor in slot 0 and everything is working as expected.

On the backplane there is an ethernet module in slot 3. This module communicates to 8 different Rockwell PLCs at 192.168.10.x. to 192.168.80.x

I can create a connection to the ethernet module in slot 3 and am able get status information from the module. I'm looking to create a connection to the PLCs through this module to reach the 192.168.x.x addresses. I feel like it should be possible through the connectionPath parameter but when I try this I only seem to be able to reach the ethernet module.

I am trying to follow this guide without success.
https://docs.inductiveautomation.com/display/DOC80/Allen-Bradley+Connection+Paths

In my main plc on the 172 network I have a series of msg instructions to pull data using a CIP data table read with a path of:
IO_Network, 2, 192.168.80.10, 1, 0
where IO_Network is the slot 3 from above.

I could expand this stepping stone method to add the additional data I want but it would be more organized and straight-forward to establish a device connection path to each end unit.

What model ethernet cards? (Asking because the 1756-ENET and 1756-EWEB cannot do the bridging you want, IIRC.)

What have you tried for connection paths? I would expect it to be something like 1,3,2,192.168.x.y or 1,3,2,192.168.x.y,1,0.

The '2' in the 3rd position might need to be a '3' or a '4', depending on the DLR/dual-IP options on the ethernet card in slot 3.

Your other option would be to bridge from one network to the other with a multi-NAT firewall router. With this you could set up a NAT rule for each WAN address to pass you through to the LAN address of the other PLCs.

You would have to consider what security risks this would introduce - if any - and apply firewall rules accordingly.

Thank you pturmel.

1,3,2,192.168.x.y did the trick. My previous attempts used numerous different combinations but all ended in 192.168.x.y,1,0. My plc msg instruction always included the ending ",1,0" since I thought it needed to know to go to slot 0 of the final destination.

For reference it is a 1756-EN3TR card.

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