The error “Can’t connect to local MySQL server through socket ‘/var/lib/mysql/mysql.sock’” typically indicates that the MySQL server is either not running or that the client can’t find the correct socket file. First, verify that the MySQL server is active. You can do this by executing `systemctl status mysql` or `service mysql status`. If the server is not running, you can start it with `systemctl start mysql` or `service mysql start`. If the server is already running, confirm that the socket file is configured correctly in your MySQL configuration file (usually located at `/etc/my.cnf` or `/etc/mysql/my.cnf`) under the `[mysqld]` section. Look for a line that specifies the socket path (`socket=/var/lib/mysql/mysql.sock`) and ensure it matches what is referenced in your client configuration (e.g., in PHPMyAdmin or command-line options).

If you’re still encountering issues after ensuring that the MySQL service is running and the socket paths are correct, it could be worth checking file system permissions on `/var/lib/mysql/` and confirming the ownership is set to the MySQL user (`mysql:mysql`). If the socket file doesn’t exist, you may need to check the MySQL error logs (typically located at `/var/log/mysql/error.log` or `/var/log/mysqld.log`) for any hints on why the server failed to start properly or isn’t generating the socket. It’s also crucial to ensure that SELinux isn’t interfering—temporarily setting it to permissive mode can help you diagnose this quickly. If the socket file still cannot be created, you might need to investigate if a recent configuration change or package update is causing the issue, and consider checking for conflicting MySQL installations if applicable.