


Why Can\'t I Connect to My MySQL Database? Troubleshooting the \'No Connection Could Be Made\' Error
Oct 31, 2024 pm 08:56 PMTroubleshooting "No Connection Could Be Made" Error in MySQL
When attempting to establish a remote connection to a MySQL database, you may encounter the error "No connection could be made because the target machine actively refused it." This error typically arises due to misconfigurations in the MySQL server settings or network connectivity issues.
To resolve this issue, follow these steps:
1. Check MySQL Server Configuration
- Ensure that your MySQL server is listening on the correct port (3306 by default).
-
In the MySQL configuration file (my.cnf), check the following settings:
- bind-address: Configured to 0.0.0.0, which allows connections from all IP addresses.
- skip-networking: Ensure it is commented out (#skip-networking).
2. Verify Network Connectivity
- Confirm that your MySQL server can communicate with your application server via the network.
- Check firewall rules to allow incoming connections on port 3306.
- Use a network diagnostic tool like ping or netstat to verify connectivity.
3. Update MySQL User Permissions
- Ensure that the user attempting to connect has the appropriate permissions on the remote database.
- Grant the user access using the following statement:
<code class="sql">GRANT ALL PRIVILEGES ON <database_name>.* TO <username>@'<host>' IDENTIFIED BY '<password>';</code>
4. Restart MySQL Server
- After making any changes to the MySQL configuration file, restart the MySQL server to apply the settings.
5. Additional Considerations
- If you are connecting to a MySQL server over the public internet, consider implementing additional security measures, such as SSH tunneling or VPNs.
- Check the MySQL error log for any additional diagnostic information that may be helpful in troubleshooting.
The above is the detailed content of Why Can\'t I Connect to My MySQL Database? Troubleshooting the \'No Connection Could Be Made\' Error. For more information, please follow other related articles on the PHP Chinese website!

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