Introduction
The client's websites began going down regularly in the morning. The issue appeared to be yet another web server outage, but it was happening at such consistent intervals that it couldn't be dismissed as a coincidence.
What went wrong
At 5:30 a.m., the control panel's automatic update was triggered. It restarted the network services and Nginx. After that, Nginx started up before the server had time to obtain the correct IP address. As a result, HTTPS was temporarily unavailable, and the websites appeared to be down.
Diagnostics
- The downtime was compared with the dashboard update schedule;
- access/error logs have been checked;
- The startup procedure for network services and Nginx has been verified;
- domain responses were verified after manual restoration;
- The issue has been resolved in WordPress itself or the website's code.
What has been done
- Auto-update of the panel has been disabled in safe mode;
- Added an Nginx auto-restart mechanism;
- domain availability has been checked;
- A plan has been developed to bind to a specific IP address or change the `listen` directive so that Nginx is not dependent on a network startup race condition.
Result
The outages no longer seemed like a mystery. The cause was identified by analyzing the logs and the timeline, after which the site returned to normal operation, and the risk of recurrence was reduced through technical fixes.
What to monitor next
After such incidents, it is important to check the panel updates, restart network services, and verify nginx behavior after a reboot or service restart.