How to Automate Let's Encrypt Renewal Monitoring on Nginx (The Robust Way)
We’ve all been there. It’s Monday morning, you haven’t had your coffee yet, and Slack is blowing up. Users are seeing “Your connection is not private.” The CTO is asking why the site is “hacked.” Your boss’s boss is cc’d on something. You check the box. Nginx is running. The app is fine. Load averages are low. Then it hits you: The Certbot cron job failed silently. Maybe the ACME challenge timed out. Maybe Nginx didn’t reload to pick up the new cert. Maybe DNS propagation was slow. Maybe Mercury was in retrograde. Doesn’t matter—production is down because of a 90-day text file, and you look incompetent. ...