It’s annoying when our servers go down for whatever reason, but when they do, I like to find out about it before readers start writing to tell me. In fact, I’d like to know right away, so I can dive into fixing the problem before many people are turned away. For many years now, I’ve used Simon, from Dejal Systems, to watch my servers and notify me in various different ways, including spoken alerts on my Mac, email messages, and Twitter direct messages. But Simon can also take the generalized concept of watching a server and pare it down to watching a specific Web page for changes, and, even more specifically, watching a particular portion of the page for changes. That’s key, since a lot of pages have dynamic elements that change constantly while the page’s main content remains relatively static.
Dejal has just released Simon 3.0; I won’t describe it further here, since you can go read about it at “Simon 3.0 Monitors Servers More Closely” (5 November 2010). Suffice it to say, then, that if you can imagine any situation where you’d want to know if a particular Internet service stops working, or if there’s any change on a Web page (even something like a stock price changing), you’ll want to check out Simon. It’s an extremely powerful and flexible program, and worth exploring.