Step 1 Run the /etc/init.d/mysql stop command on the system data node to stop the MySQL process.
Step 2 Run the /etc/init.d/mysql start command on the system data node to start the MySQL process.
Step 3 Run the ps ef|grep mysql command to check whether the MySQL process is running properly.
Step 4 Check whether reading and writing data can be performed successfully. If yes, the fault is removed. If no, contact technical support engineers.