ServersUp.net is described as 'can check a number of different services on different hosts to make sure those services are up and running. It will send alerts when the statuses change' and is an website in the Network & Admin category. There are more than 50 alternatives to ServersUp.net, not only websites but also apps for a variety of platforms, including SaaS, Windows, Linux and Android. The best alternative is UptimeRobot, which is free. Other great sites and apps similar to ServersUp.net are Pingdom (Paid), Freshping (Free), StatusCake (Freemium) and HetrixTools (Freemium).
Dashboard with 50 Monitors, Checked Every 5 Minutes, Totally Free. Monitor HTTP(S), Ping, Port and check Keywords. Get alerted via e-mail, SMS, Twitter, web-hooks or push. View uptime, downtime and response times.
Pingdom web site monitoring and other infrastructure for you and instantly let you know when anything goes wrong. Measure uptime, downtime, and the performance of your website as experienced by visitors.
StatusCake.com is a free website monitoring tool which allows users to track up to 10 websites and get alerted when their site is down or is having trouble. Downtime root cause analysis is included in the free plan to help users diagnose and fix issues.
All of your MX record, DNS, blacklist and SMTP diagnostics in one integrated tool. Input a domain name or IP Address or Host Name. Links in the results will guide you to other relevant tools and information.
NetCrunch is an all-in-one and agentless network, server, application, log, file and web monitoring suite, capable of monitoring more than 1 million elements at once. It runs on Windows Server and only needs 4GB of RAM and 4 cores.
Pingbreak is an original and free monitoring service. Get notified through Twitter if your website is down. Pingbreak checks all of your websites each minute and alert you instantly by Direct Message (DM).