Fixing ‘Can’t Connect to Local MySQL Server’ Error

MySQLmysql-5

I tried restarting the Mysql server but its not working for me. I am sure the server is running and the permissions on the folder /var/lib/mysql/ are correct (777).

When i tried to open the file mysql.sock, its giving me an error saying the file may be corrupt.

Please help me to log on to the mysql server.

Best Answer

First: Make sure that the owner of /var/lib/mysql and its files and subdirectories is mysql user of mysql group

to do that run the following command:

chown mysql:mysql -R /var/lib/mysql/*

Second: change write permissions to rwxr-xr-x (755) for mysql directory, and all its files and subdirectories, by running the following command:

chmod 755 -R /var/lib/mysql/*

now start mysql service

service mysql start

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Thesqld – cannot connect to socket after changing datadir location

The problem is the mysql client program configuration. You can specify the --socket=/NEW_DIR/mysql/mysql.sock command-line option or add it under the [mysql] section of your my.cnf file.

Please look at the documentation for specifying options through option files: http://dev.mysql.com/doc/refman/5.0/en/option-files.html

Since changing the socket path affects all the client programs, then it will make sense to update the global my.cnf and set the socket option under the [client] section.

MySQL – Differences Between mysqld_safe and mysqld

As we all know, mysqld_safe and mysqld are very different

mysqld : The database server instance daemon

mysqld_safe : Control program that examines and sets the environment for mysqld to execute. The mysqld executable is actually launched in a loop. When mysqld terminates, the mysqld_safe program will examine the return results and decide whether

mysqld terminated normally (intentional shutdown), leaves mysqld_safe
mysqld terminated abnormally (crash or kill -9 of mysqld)
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Why is it important to have mysqld and mysqld_safe using the same MySQL version?

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The same scenario could possibly be the case for Oracle's (ugh, still hate saying that) mysqld and mysqld_safe. There could be improvements from one major release to another that would be removed if the mysqld_safe was older.

Rather than exploring the possibilities of using a old mysqld_safe and a new mysqld (or vica versa), please make your life simple and reinstall MySQL 5.5.30 from scratch.

Before doing so, please run

updatedb
locate mysqld_safe

in Linux and see if there are two lingering. If there are, get the paths straightened out. Otherwise, you may have to reinstall MySQL 5.5.30.

Best Answer

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