


Why Can't I Connect to My MySQL Server: 'Host 'xxx.xx.xxx.xxx' is not allowed'?
Cannot Connect to MySQL Server: "Host 'xxx.xx.xxx.xxx' is not allowed"
In an attempt to establish a remote connection to a MySQL server, you encounter the error message: "Host 'xxx.xx.xxx.xxx' is not allowed to connect to this MySQL server." Despite having a user entry with both 'localhost' and '%' as host values, the problem persists.
Explanation
This error typically arises as a security measure. To ensure the security of your database, it is recommended to limit access to specific hosts and restrict the use of wildcards ('%' or '_'). The default privileges for the 'root' user often include an entry with Host='localhost' and User='', which takes precedence over entries with more general Host values.
Solution
To resolve this issue, consider the following steps:
- Create a New Administrator Account:
Create a new administrative user with specific host access, such as 'localhost' or '%%' (for all hosts). Grant the necessary privileges to this user.
mysql> CREATE USER 'monty'@'localhost' IDENTIFIED BY 'some_pass'; mysql> GRANT ALL PRIVILEGES ON *.* TO 'monty'@'localhost' -> WITH GRANT OPTION; mysql> CREATE USER 'monty'@'%' IDENTIFIED BY 'some_pass'; mysql> GRANT ALL PRIVILEGES ON *.* TO 'monty'@'%' -> WITH GRANT OPTION;
- Limit Access to Specific Hosts:
When creating users, specify the exact hosts or IP addresses that they are permitted to connect from. This ensures that unauthorized access is restricted.
- Delete Wildcard Entries:
If there are any user entries with wildcard hosts ('%' or '_'), it is recommended to remove them to enhance security. Once removed, issue a FLUSH PRIVILEGES statement to reload the grant tables.
By implementing these measures, you can establish a secure connection to your MySQL server and mitigate the risk of unauthorized access.
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