Cisco Umbrella - Cisco Umbrella is a cloud security platform that provides the first line of defense against threats on the internet.
Pingdom - With website monitoring from Pingdom you will be the first to know when your website is down. No installation required. 30-day free trial.
WebTitan - WebTitan is an advanced DNS based web content filter and web security layer that blocks malware, ransomware and phishing attempts as well as providing web content control. Cloud and gateway versions available.
StatusCake - Website Uptime Monitoring & Alerts – Free Unlimited Downtime Monitoring
DNSFilter - DNSFilter offers DNS-Based Content Filtering & Threat Protection.
Better Uptime - We call you when your website goes down