We've been getting downtime alerts throughout the day at random intervals yesterday, but the issue resolved itself before we had a chance to login to find the problem. While logged in to our busiest server digging through the logs, we received a downtime alert and were able to check what was causing the issue. One of the websites hosted on the server was using up all of the PHP processes and was causing all PHP-based websites to fail due to hitting the limit.
To address this, we've made the following changes to all of our servers:
1) Tripled the PHP process limits to ensure more connections per server (this will be tweaked as needed based on resource usage and load).
2) Put a hard limit of 10 connections per IP address per domain (previously unlimited) so no single visitor can use up all of the resources on the server.
3) Restricted each domain to maximum of 15 connections per second so no single domain can use up all of the resources on the server.
We've had these settings configured for over 12 hours with no noticeable impact to user's traffic, but we can adjust these settings as needed. If you find your visitors are experiencing issues when accessing your site due to the volume of traffic you receive, please open a ticket and we will tune this to better suit your legitimate traffic.
Thank you for your understanding and we apologize for the issues encountered.
-The AFreeCloud Staff