I did a test I was running one NXT node on my windows computer (A) and another one on a local Windows VM (B) running on the same computer. To do this test I disconnected the connexion.
I wanted to be able to add the IP of B as a peer in A. I did set up well the nxt.propreties file. But it didn't work. To make it work I had to update the firewall manually and add this two lines:
After that it worked perfectly. Is this a normal behavior?