Okay... at this point I'm confused. I have an aws ec2 server an 2 different rds database.

The first mariadb database is on port 33060

The second mariadb database is on port 3306

At this point I have both security groups set to 0.0.0.0/0 for everything.

But both modifying wp-config.php and the wordpress website startup screen with the wordpress database credentials thows: "Error establishing a database connection"

On both databases (first and second) I have a database called 'wordpress'. When I run:

• SHOW GRANTS FOR 'user'@'server-ip-address';

I can see my user has SELECT, INSERT, UPDATE, DELETE, CREATE, REFERENCES, INDEX, ALTER, CREATE VIEW, SHOW VIEW, CREATE ROUTINE, and ALTER ROUTINE from my remote server host.

This is a dev database, so I really don't care about permissions. That said, permissions look correct.

So I moved onto the server. A simple command to run:

• telnet -l username first.database.address.us-backeast-33.com 33060

• (sleep 1;echo username;sleep 1;echo password;) | telnet second.database.address.us-backeast-33.com 3306

Both telnet sessions can be established from database to server. I'm at a loss why this is erroring out.

Edit: issue was with SELinux not allowing proper writing of files. Solution can be found here:

https://techblog.jeppson.org/2016/10/install-wordpress-centos-7/