background purpose: I want to restrict inbound connection to MYSQL server only for specific host by setting inbound rules of windows firewall.
MYSQL server port is open on 3306.
However, when I open firewall setting, I can see two ports are opened on 3306 and 33060 as follows:
what is that?
This connection port is used by the mysql clients to connect to the mysql server. However, in difference to port 3306. These connection uses the so called x-protocol. This port is supported by clients like Mysql-Shell or community Mysql-Connectors, while the mysqlclient and tools like mysqldump are using the classical Port. The x-protocol is a alternate mysql query interface that includes a alternate API called X-DevAPI. It allows you to access the data in json and also supports SQL. However, you have to allow it in your firewall settings unless you are deactivating this port/protocol on your mysql-server. So to sum it up for you: The x-protocol and the port 33060 is optional and not necessary.
Reference for general information about mysql Ports: https://dev.mysql.com/doc/mysql-port-reference/en/mysql-ports-reference-tables.html
Reference on X-Protocol: https://www.percona.com/blog/2019/01/07/understanding-mysql-x-all-flavors/
The list of ports used by MySQL are available here: https://dev.mysql.com/doc/mysql-port-reference/en/mysql-ports-reference-tables.html
For typical usage, you only need port 3306. Check your server configuration files to see what ports it's listening to.
