Ansible - Radically simple configuration-management, application deployment, task-execution, and multi-node orchestration engine
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.
Salt - Fast, scalable and flexible software for data center automation
StatusCake - Website Uptime Monitoring & Alerts – Free Unlimited Downtime Monitoring
Puppet Enterprise - Get started with Puppet Enterprise, or upgrade or expand.
Better Uptime - We call you when your website goes down