Uptime monitoring
Never let an SSL certificate expire again
Auto-renewal fails more often than anyone admits: a changed DNS record, a firewall rule blocking the ACME challenge, a cron job that stopped running. An SSL monitor checks the live certificate on your domain and warns you before it expires.
What to monitor on SSL certificate
- 01Days until expiryAlert when fewer than your warning threshold remain (default 14 days).
- 02Handshake successCatch broken chains and mismatched hostnames immediately.
Set it up
Create an SSL monitor
Enter the hostname, e.g. example.com.
Set the warning window
config.days_warning — 14 days by default, raise it to 30 for manually renewed certificates.
Recommended alerts for SSL certificate
- Certificate expires within the warning window
- TLS handshake fails
Send alerts to
SSL certificate monitoring FAQ
Does it check certificates on non-standard ports?
Use host:port as the target, e.g. mail.example.com:993.
How often is it checked?
Expiry changes slowly, so an interval of several hours is plenty; you can still choose any interval your plan allows.
Know before your users do.
Free forever for 3 servers and 10 monitors. No credit card. Install the agent in under a minute.