Recently came across two articles about free website monitoring tools, Top 10 Free Website Uptime Monitoring Services, from Design Live, and 12 Excellent Free Tools for Monitoring Your Sites Uptime, from Six Revisions. Both articles are good for identifying possible services to use. Both have some overlap in the services they document. (I’ve also covered this topic before, Website Monitoring and Support Software).
However, articles like this are a mile wide and an inch deep. For example, some of these free services take up to 60 minutes to notify you if there is a failure. There also could be lag time between the time the monitoring service is notified and the time they send an email or SMS to you. At least one solution involves placing a file on your web server, which yields more detailed data to monitor. In short, the free option for many of these services is limited in ways that might not be useful. So it is caveat emptor, or buyer beware.
I have played with Montastic and Basic State. Montastic is fine. Basic State yesterday caught a server failure within fifteen minutes, which is great for free. Their daily status emails also are useful. I’d also check out the comments on these articles for more vendors. I found Server Density that way.
My recommendation is to compare all services, try the services that meet your needs and then, if you need to, pay for the service. Despite what these articles promise, it is possible but unlikely you will find a free service that does exactly what you want. But free is enough to try these services, to find what works for your website(s).
