SSL Certificate Monitoring: A Complete Guide

Why SSL Monitoring Matters

An expired SSL certificate will:

• Display scary browser warnings to your users
• Break API integrations that enforce certificate validation
• Tank your SEO rankings (Google penalises insecure sites)
• Erode customer trust

Common SSL Issues

1. Certificate Expiry

The most common issue. Certificates typically last 90 days (Let's Encrypt) or 1 year (commercial CAs).

2. Certificate Chain Problems

Missing intermediate certificates cause validation failures on some devices.

3. Mixed Content

Your site serves HTTPS but loads resources over HTTP.

4. Weak Cipher Suites

Outdated TLS versions (1.0, 1.1) are security risks.

Monitoring with UptimeGuard

UptimeGuard checks your SSL certificates automatically:

• Expiry alerts — 30, 14, 7, and 1 day before expiry
• Chain validation — detects missing intermediates
• Protocol checks — flags TLS 1.0/1.1 usage
• Certificate transparency — monitors CT logs for your domains

Automating Renewals

# Certbot auto-renewal with post-hook
certbot renew --post-hook "systemctl reload nginx"

Combine automated renewals with UptimeGuard monitoring for defence in depth. Even if auto-renewal fails, you'll know about it with time to fix it.