Use security group settings to block external network access to a specific port on the server.

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Entry point:

Log in to the Management Center, Business Management--Security & Monitoring--Security Group 

Click the Add button to add a security group. After creating it, click [Rules] to add the corresponding information.

This article's example is to prohibit external network access to server port 3306, but separately allow specified IP access. In actual use, just set the port you need.

After setting, all access to server port 3306 will be intercepted.

Notes on current port settings:

Target port: The port on the server that you do not want others to access.

If you need to intercept other service ports, please refer to:

Common ports of our company's servers:

21 (ftp port)

80 (website web port)

3306 (mysql port)

1433 (sqlserver port)

33890 (windows system remote port)

8080 (default port of our company's WDCP system)

Select the port to intercept according to your needs

If you want to allow a specific IP or IP range to access the port separately, after setting all IPs to prohibited as above, refer to the following figure:

The configured IP will be allowed to access this port.

Notes on IP range settings:

Source IP filled as 118.124.8.0/24   means 118.124.8.*

Source IP filled as 118.124.0.0/16   means 118.124.*.*

Deploy Rules

After successful addition, click the "Deploy" button and select the server to which the deployment will be applied.

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