Monitor SSL Certificate Renewal Cron Jobs
Prevent certificate expiry downtime
The problem
Certbot renewals run as cron jobs and work silently for months. When a DNS provider change or permissions issue breaks the renewal, you don't find out until browsers show security warnings and customers can't access your site.
# Certbot auto-renewal runs twice daily
$ crond-agent wrap --name "certbot-renew" -- certbot renew --quiet
[crond.io] monitoring "certbot-renew" (every 12h)
[crond.io] ping sent ✓ (exit 0, 2.1s) — no renewals needed
# 29 days later: renewal attempt
[certbot-renew] Failed to renew: DNS challenge failed
[crond.io] FAILURE ping — exit code 1
[crond.io] email sent → ops@example.com
# You fix it with 2 days to spare
How crond.io helps
crond-agent monitors every certbot run. Even when no renewal is needed, it confirms the job executed successfully. When a renewal actually fails, you're alerted immediately — days before the certificate expires.
- ✓Alert on renewal failures days before certificate expiry
- ✓Works with certbot, acme.sh, lego, and any ACME client
- ✓Exit code tracking catches silent failures in renewal hooks
- ✓Grace period handles legitimate skips (no renewal needed)
- ✓Email and webhook alerts for urgent certificate issues
Start monitoring in 60 seconds
Free tier includes 10 monitors. No credit card required.
$get-started --free