Two arduino with ethernet shield linked together

Good morning,
I searched the net and in the forum but could not find any examples that did for me.
I would like to transfer the state of an input pin of an Arduino board equipped with Ethernet Shield to other Arduino boards (also with Ethernet shield) through a LAN network company "fully open" have free port filtering.
Example: Arduino -----> LAN -----> Arduino
The examples refer Arduino IDE used as a web server or as a client but always interfaced to a PC using the HTTP protocol.
With the same commands or server.write, can I communicate with each other more Arduino and possibly use the pc only for debugging (serial monitor, or mode 'client)?
In other words, I can replicate the status of a digital input (either HIGH or LOW) output of more 'Arduino Client connected via LAN?
Unfortunately I have not the second Shield so I can not do some testing, but I would like very much your suggestions to figure out which type of protocol to use. Unfortunately, given the distances involved and the architecture of the system is not 'possible to use other transmission systems (RS232, etc.).
Thank you, Andrea.

That shouldn't be a problem. If you are looking for speed, probably the best is UDP, but delivery is not guaranteed unless the receiving device sends a packet back.

If you are looking for the occasional "open - send request - receive response - close" protocol, http may be your best bet.

My GET method client code should play well with my server code. You will need to change the code to suit your requirements.
The mac addresses are different, but the static ips are identical in those examples. Change one or both ip addresses.

The thing you must remember is:
All mac addresses on a localnet must be unique.
All ips on a subnet must be unique.

Thank you for your rapid response.
I'm waiting for the second ethernet shield to try your suggestion!