Why is the server dropping connections?

Question

linux

Faced with two, at first glance, unrelated phenomena.

There is a server on Debian 10 on which a Minecraft server is deployed. This server is started by me via SSH with a command using screen. Today oddities began, the Minecraft server began to cut off all connections and fall. Drops my ssh connection at the same time. Where to look and why?

The day before, I set up authorization by public key. The problem seems to be here, but I'm not sure which directive in sshd_config to look at

Answer 1

By default, SSH drops the connection after 3 minutes of inactivity ( link ). Write on your computer in ~/.ssh/config :

ServerAliveInterval 60  # период отправки сигнала keepalive в секундах
ServerAliveCountMax 120  # количество отправок сигнала

Thus, the connection will last two hours with inactivity. If this is your problem, then this should help.
Authorization by key could not cause "falls" of the server. And what do you mean by fall? Server unreachable over network, Minecraft server stops responding?