Praj's Blog

PHP database can’t connect to localhost but 127.0.0.1 works

There are many reasons for this, so first check that MySQL/MariaDB is running properly, that you are using the correct credentials and that the the appropriate user@localhost has access.

Also check you aren’t using skip-name-resolve and bind-address in your my.cnf file if accessing from outside of the localhost. These are things you will find with a google search.

Apart from this one other reason why 127.0.0.1 will work and localhost will not work is if you are using something other than the default socket=/var/lib/mysql/mysql.sock location in your my.cnf.

If that is the case, you’ll need to update the relevant default_socket= parameter in php.ini (for each driver) to match that socket – see the entries under my.cnf [mysql] and [mysqld] sections for the socket parameter. This is more likely to occur if you are using MariaDB for example.