


Permission Denied Error when Connecting to Database via Localhost
In an attempt to connect to a MySQL database using PHP, users often encounter the dreaded "Error: Unable to connect to MySQL. Debugging errno: 2002 Debugging error: Permission denied" issue when executing the script locally, despite successful execution on the command line.
Delving into the Issue
Upon investigating this puzzling dichotomy, it emerges that SELinux security policies are the underlying culprit. By default, the "httpd_can_network_connect_db" policy is disabled, preventing the web server from establishing a connection with a remote database.
Verifying the Policy
To confirm this assumption, execute the following command:
getsebool -a | grep httpd
If "httpd_can_network_connect_db" is set to "Off," proceed to the solution below.
Resolving the Issue
To rectify the situation, the policy must be enabled permanently. This is achieved using the following command:
setsebool -P httpd_can_network_connect_db 1
By allowing the web server to communicate with the remote database, this modification resolves the permission denied error, paving the way for seamless database connectivity from within the web application.
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