Message path help

Thanks for any help! I can usually figure these out, but after an hour of misses I don't have any more tricks up my sleeve. I've read some great tips here including this one:

http://www.plctalk.net/qanda/showpost.php?p=817009&postcount=9

Over the holiday shutdown, we migrated a PLC5 to control logix. The previous PLC5 read 16 INTs from a L33ER across our plant network. I cannot seem to get the L81E to do the same.

The trouble for me seems to be that the Plant EN2T is in Rack2, there was no room in Rack1 which also has the processor.

So the path is:
L81E(Rack1)192.168.1.10 -> EN2T(Rack2)192.168.1.20 -> slot10(Plant EN2T) -> 172.16.xx.xx > NAT-> 192.168.1.10(L33ER)

The NAT didn't seem to matter to the PLC5, so it shouldn't here, correct? The PLC5 just went to 172.16.xx.xx slot 0 .

cncsparky said:

Thanks for any help! I can usually figure these out, but after an hour of misses I don't have any more tricks up my sleeve. I've read some great tips here including this one:

http://www.plctalk.net/qanda/showpost.php?p=817009&postcount=9

Over the holiday shutdown, we migrated a PLC5 to control logix. The previous PLC5 read 16 INTs from a L33ER across our plant network. I cannot seem to get the L81E to do the same.

The trouble for me seems to be that the Plant EN2T is in Rack2, there was no room in Rack1 which also has the processor.

So the path is:
L81E(Rack1)192.168.1.10 -> EN2T(Rack2)192.168.1.20 -> slot10(Plant EN2T) -> 172.16.xx.xx > NAT-> 192.168.1.10(L33ER)

The NAT didn't seem to matter to the PLC5, so it shouldn't here, correct? The PLC5 just went to 172.16.xx.xx slot 0 .

Click to expand...

Let me see if I understand.

New L81E is address 192.168.1.10
It talks to 172.16.xx.xx

The path is 1, 192.168.1.20, 0, 10, 1, 172.16.xx.xx ... (or is the first path specified as 2? .. can't remember what the front port is called). If there are redundant ports, and they are set up as redundant, I think the port is called .. 3? If they are set up as separate ethernet addresses, I think they are 1 and 2 in the path but 0 and 1 in the config of the card. I have only played with one of these and it was brief so I could be way off base here

Agreed that the NAT should invisible to the ControlLogix

Out the front port, to 192.168.1.20, to the backplane, to slot 10, out the ethernet port, to 172.16.xx.xx ... is what I believe the path should be. I assume that you can't use RSLinx to browse to the target NAT for some reason.

What is your network mask? Is it possible that the L33ER is responding but your network mask does not allow the ControlLogix to see it? The NAT should respond to slot 10 at 192.168.1.20, just like it did before. Did you match the old PLC5 network mask and gateway?

192.168 is 1100 0000, 1010 1000
172.16 is 1010 1100, 0001 0000
Match should be 1001 0011, 0100 0111
no info on the last 1 octets so I used 0.0

147.71.0.0 .. if you want it to match 192 and 172, 168 and 16 ... but this could cause you other problems if other networks match .
I have no confidence in this mask. It seems too weird

But I listed it in case it triggers another thought on your side