Firewall rules for MariaDB replication.

For mariadb replication to work, firewall ports need to be open on the primary

and secondary server.

Three required steps

1. Configuration

2. Testing ports are open

3. Testing communication between servers

4. Configuring Ports on Primary and Secondary Servers

Open Ports on Primary Server:

sudo firewall-cmd --zone=public --add-port=3306/tcp --permanent

sudo firewall-cmd --zone=public --add-port=4567/tcp --permanent

sudo firewall-cmd --reload

Open Ports on Secondary Server:

sudo firewall-cmd --zone=public --add-port=3306/tcp --permanent

sudo firewall-cmd --zone=public --add-port=4567/tcp --permanent

sudo firewall-cmd --reload

1. Testing if Ports are Open

Check Port 3306:

nc -zv <server-ip> 3306

Check Port 4567:

nc -zv <server-ip> 4567

Replace <server-ip> with the actual IP address of your primary or secondary server. You should see a message indicating a successful connection if the ports are open.

1. Testing Communication Between Primary and Secondary Servers

From Primary Server to Secondary Server:

nc -zv <secondary-server-ip> 3306

nc -zv <secondary-server-ip> 4567

From Secondary Server to Primary Server:

nc -zv <primary-server-ip> 3306

nc -zv <primary-server-ip> 4567

Ensure that both servers can communicate with each other on the specified ports. If the connection is successful, it indicates that the ports are correctly configured and open for replication.