问题
I'm receiving the error
Failed to connect to MySQL: Permission denied
When connecting from PHP with MySQL, MySQLi and PDO to a remote MySQL host.
However, if I connect to the same host, with the same credentials through MySQL from the same host on the command line it works perfectly.
So I'm making the assumption its a PHP config problem?
Connecting FROM
PHP 5.6.40 (Client API version => mysqlnd 5.0.11-dev)
MySQL 5.5.59
Connecting TO
PHP 5.6.23 (Client API version => mysqlnd 5.0.11-dev)
MySQL 5.5.52
Anyone got any ideas why I can connect from the command line to MySQL but not from PHP to the same host with the exact same credentials?
回答1:
I guess that you have SELinux enabled on your server. By default it doesn't allow apache process to initialize outgoing network connections.
Copy of an answer from https://serverfault.com/a/456875/442205
To check SELinux
sestatus
To see what flags are set on httpd processes
getsebool -a | grep httpd
To allow Apache to connect to remote database through SELinux
setsebool httpd_can_network_connect_db 1
Use -P option makes the change permanent. Without this option, the boolean would be reset to 0 at reboot.
setsebool -P httpd_can_network_connect_db 1
来源：https://stackoverflow.com/questions/57270169/php-mysqli-permission-denied-but-working-from-mysql-cli