MARIADB - https://support.plesk.com/hc/en-us/articles/213403429-How-to-upgrade-MySQL-MariaDB-from-5-5-to-5-6-5-7-on-Linux-

    MYSQL ACCESS

    GRANT ALL PRIVILEGES ON *.* TO ''@'localhost' IDENTIFIED BY 'PASSWORD' WITH GRANT OPTION;

IPTABLES

https://www.digitalocean.com/community/tutorials/how-to-migrate-from-firewalld-to-iptables-on-centos-7

ipf -f

https://www.digitalocean.com/community/tutorials/how-to-protect-ssh-with-fail2ban-on-centos-7

CLOUD9 - wget -O - https://raw.githubusercontent.com/c9/install/master/install.sh | bash

    Recreate SSH Keys