Socket.io: Constantly disconnecting. How to catch the cause and has anyone had something similar?

Question

JavaScript

There is a chat on Socket.io I turn on
the websocket with the command
./yii ws/start > /dev/null &
it starts the standard socket server from the documentation on port 8090.
Apache set up proxying from ws.site.ru:80 to localhost:8090. all ports are closed on the server except 80 and 22
when I start the socket server, everything works. chat connects. After some time, the connection stops working. htop shows that the script is hanging in memory and running. but the chat page can't connect.
What can be seen, how to track the causes? I tried to connect from a working computer, the same problem. As if the port is being closed.

Answer 1

There was a problem, I decided to reconfigure the connection times from scratch! Akubintsev is correct.

Answer 2

Apache logs

Answer 3

Why apache and not nginx for proxying? Have you configured connection timeouts?