you don't need to change any setting on the router.
See , if you connect the computer to the port number 2 of the router. It will go online without any problem.
if you connect the computer to port 3 , it will go online without changing any settings for ethernet.
everything will depend the IP address. If you connect the computer to the router , your computer will get the IP address from the router.
and both will start communicating.
Same way your printer will get the IP address from the router.
and they will talk to each other.
Now when you connect the printer to the router , you will need to check the settings of the printer and your computer should be set to network printer.
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