This server has been undergoing a brute force attack since last weekend. Plugins and modifications to .htaccess have been installed and blocked some attempts. While we have been able to slow down the usage of the resources, there are episodes in which the CPU is jammed for 15-20 minutes, thus taking down the server.
I apologize if the server is not available at all times. Monitoring continues but there are too many false IP addresses being used to block IPs.
Update: Blocking China and Russian Federation traffic at this time. While this has dramatically slowed down the brute force attack, error logs continue to grow as attempts are made to use a file accessible only through a single IP address. All other IPs are blocked.
Decided to switch to Cloudflare DNS and protection. We will see what happens.