How to set maximum FTP connections per IP address via WHM?

Setting a maximum number of FTP connections per IP address helps prevent any single client from consuming too many server resources. This is especially useful for stopping abusive bots, misconfigured FTP clients, or denial-of-service attempts from overwhelming your FTP service.

Step 1: Log in to WHM

Open your browser and navigate to https://your-server:2087. Enter your root credentials to log in.

Step 2: Navigate to FTP Server Configuration

In the left-hand menu, go to Home » Service Configuration » FTP Server Configuration.

Step 3: Set Maximum Connections Per IP Address

This setting is available when your server uses Pure-FTPd as the FTP server. Locate the Maximum Connections Per IP Address field and enter the maximum number of simultaneous connections you want to allow from a single IP address.

• The default value is typically 5 or 8, depending on your WHM version.
• A value of 0 removes the limit (not recommended).
• A lower value (e.g., 3-5) is recommended to prevent abuse while allowing normal multi-threaded FTP clients to function.

Step 4: Save Changes

Scroll to the bottom of the page and click Save. The new limit takes effect immediately.

Important Notes

• ProFTPD servers: If your server uses ProFTPD instead of Pure-FTPd, this option will not appear. Instead, use the Maximum Number of FTP Processes setting to limit the total number of FTP connections server-wide.
• FTP must be enabled: The FTP Server Configuration page is only available if FTP services are enabled. Check this in Home » Service Configuration » Service Manager.
• This setting applies server-wide and affects all cPanel accounts.
• Some FTP clients (like FileZilla) open multiple connections simultaneously. Setting the limit too low may cause transfer failures for legitimate users.

Troubleshooting

• Clients getting "Too many connections" errors: Increase the limit slightly, or ask the user to reduce the number of simultaneous connections in their FTP client settings.
• Setting not visible: Ensure your server is running Pure-FTPd. You can check which FTP server is in use on the FTP Server Configuration page itself.
• Changes not taking effect: Restart the FTP service via Home » Service Configuration » Service Manager or by running service pure-ftpd restart via SSH.

For more information, refer to the official cPanel documentation.