Added manual to add host for ssl certificate expiration alerts

README.md

@@ -42,6 +42,7 @@ The aim of this project is to have a quick guide of what to do when an emergency
 ## Alerting and monitoring
 * [How to add alerts: Alerts manual](howto/alerts_manual.md)
+* [Alert for SSL certificate expiration](howto/alert-for-ssl-certificate-expiration.md)
 * [Working with Grafana](monitoring/grafana.md)
 * [Working with Prometheus](monitoring/prometheus.md)

howto/alert-for-ssl-certificate-expiration.md

+# Alert about SSL certificate expiration
+
+## Modify list of hosts with SSL certificate
+
+By editing list inside `prometheus.jobs.blackbox-ssl.target` attribute in the role `prometheus-server` on chef, you can add or remove server from monitoring for SSL certificate expiration. By adding server there you will be receiving alerts when there is less than 30 days remain for certificate expiration.