AreMySitesUp.com is a nice, free web monitoring service that will let you monitor up to 20 URLs and e-mail or text you if it detects that any of the sites are down.
They also have a premium option for $75/year or $8/month. The premium service lets you monitor up to 60 URLs, performs the uptime check more frequently, and provides a lot more options for notification so if you want notifications to go to Twitter or an RSS feed, they’ll do that.
It also adds what it calls “keywords” which really means you can test not only whether a site is up but also whether a specific service is still running.
Here is how it works:
When you add a new site to your list (or edit an existing one), you will have the option to specify keywords. This is a string of 20 characters max. When we check your site, we will look for this specific string of characters. If we don’t find it, your site will be marked as down.What is this for?
It’s to make sure your site is really, truly online and responding as normal. Let’s say your web server is up and responding normal, but your database goes down and your site requires the database to work. Your web server might respond with “Error establishing database connection.” This is a valid response which our system may interpret as up. But clearly your site isn’t up. They keyword check would then fail and you would be notified. Powerful stuff!
I’ve been using the free service and am sorely tempted to subscribe to the premium. OTOH, over the last year I had a total of two hours of unscheduled downtime on this server, so I’m not sure it makes sense to pay that much. But if you do have a server that is critical and you don’t already have a monitoring solution, this at least seems to be fairly feature rich.
