Inline FW configuration help needed!

[Smorgan]

Hello! I am trying to put a FW 5506 inline (Routed Mode) between our corporate network and an ICS network controlled by a PLC. If I directly connect devices to the FW and assign their corresponding FW interface as the Default Gate Way traffic has no issues trans versing through the FW. However when placed inline as seen below I can only reach the 10.12.X.5 interface and nothing beyond it. I feel like a static route in the Router would help but I'm honestly a little lost. Any help would be greatly appreciated!  

** Before this FW was placed inline I had NO issues reaching the PLC from the archive server. LOL 

[RTuttle99]

You fw doesn't know how to get to the destination address as it is on both sides of the firewall. You would need to be in non-routed mode for the layout you depict. I would recommend taking the 192.168.x.X network off the router, switch and firewall. Then you would have 1 network on either side of the firewall. 

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