ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock' (2)

Platform: Linux/Unix

If you come across below errors when trying to connect MySQL then there might be couple of reasons behind it.

-bash-3.2$ mysql --user=root --password
Enter password:

ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock' (2)

One of the reason could be that MySQL server isn't running. So how do you check whether or not MySQL is running? try running below shell command and see what it reports


-bash-3.2$ ps -e|grep mysqld
30878 ? 00:00:00 mysqld_safe
30939 ? 00:58:06 mysqld
-bash-3.2$


If you see at least 2 process are running/listed from the above command then it is confirmed that MySQL is running.
What if you don't see any process(as shown below)? then the MySQL services is not at all running then try to start it and watch for errors(you can check error log for same) and resolve them before making an attempt to start.
-bash-3.2$ ps -e|grep mysqld
-bash-3.2$

Starting MySQL(easiest way :-))

/etc/init.d/mysql start

If there are no errors, re-enter the process status(ps) command once again & if the service is now running, then try connecting to MySQL and If still you are receiving the error then another reason(wasn't first one) could be if the location of the Unix socket has been changed or is different from the default location.

It might be that the location of the socket file has been changed so first one has to check the MyQL config file (/etc/my.cnf) and locate the the value for the socket parameter(you may see two socket details - for client and mysqld groups).

-bash-3.2$ more /etc/my.cnf |grep socket
socket=/var/lib/mysql/mysql.sock
-bash-3.2$

It could be that the value for the --socket option is set at the command-line when MySQL is started is different than what the client mysql is expecting in that case you have to either change the socket file path in the config file or you will have to supply the socket parameter with its path for the the client

-bash-3.2$ mysql --user=root --password --socket=/var/lib/mysql/mysql.sock
Enter password:
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 421830
Server version: 5.0.45 Source distribution

Type 'help;' or '\h' for help. Type '\c' to clear the buffer.

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