I cannot connect to the database server,

I have checked that all the database connection information is correct.

I have used iptables to allow port 3306 on the database server side.

I have added the permission to the username used to connect to the database.

Database Name: 'player_authentication_on_network'
(GRANT ALL PRIVILEGES ON player_authentication_on_network.* TO '{username}'@'{host}' IDENTIFIED BY '{password}' WITH GRANT OPTION;)

This is information about all errors -> https://pastebin.com/jRfTk3eH

And here is my config -> https://pastebin.com/s0f7ZXXU

This is 100% a networking / firewall issue, the initial connection timed out.