mariadb won't let me access from "remote"
Four things to check:


Check that the DB user allows for connecting from the remote client. A user has a both a 'user' and a 'host' component. SELECT user, host FROM mysql.user; will show your users including their hosts, i.e. the clients they allow. You can use the wildcard '%' to allow connecting from any client, or a specific IP address or hostname if you prefer that.
Make sure that the skip-networking variable is not enabled in the configuration files.
Make sure bind-address is either not enabled or pointing to a specific IP address you want to allow in the configuration files.


Once you have updated the configuration files, restart MariaDB.

Check the MariaDB documentation on configuring for remote client access for details.


Make sure the firewall on CentOS isn't blocking access:

sudo firewall-cmd --zone=public --permanent --add-service=mysql

sudo systemctl restart firewalld