Cannot Connect to MySQL Database During Configuration

At times, especially during the initial configuration or reconfiguration of your system, you might see the following message:

Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock

If you see that message, perform the following steps to restart the database and resolve the problem:

As root on the head node, restart the database:
# service mysqld restart
This command may report that it fails to either stop or restart the MySQL processes. If so, continue with the remainder of this procedure.
Enter the following command to find MySQL processes:
# ps -eaf | grep mysql
Three processes should be listed: grep, mysqld_safe, and mysqld. If you do not see mysqld_safe and mysqld, proceed to step 4.
Use the process ID (PID) of /usr/libexec/mysqld (the number just after the process owner name) to kill mysqld manually. If the mysqld process is not listed, but there is a mysqld_safe process, use that PID instead.
# kill mysqld_PID
This process should kill both mysqld and mysqld_safe.
Restart the mysqld service:
# service mysqld start
The command you were trying to run should now be able to connect to the database.

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