How can I know if my site is down?

Question

I would like to be alerted if my site is down (for example have an email sent to me).

The site is written in asp .net it is deployed on a dedicated server, windows 2008 with IIS 7

Answer 1

we use Pingdom, there is a Free plan, it checks your site every 5 minutes, but you can check only one site, url : http://www.pingdom.com/

With BasicState you can check unlimited number of sites and check frequency is 15 minutes, url : http://basicstate.com/

Update: There is another great site: http://www.monitor.us/free-IT-system-monitoring

Answer 2

If you have a Linux machine in your environment, this should be a relatively simple task in any scripting language that can call out to the shell. Take a look at the wget and sendmail commands for retrieving files over HTTP and sending e-mail, respectively.

The idea is to try retrieving something like index.html from your site. If the attempt fails, the script sends you an e-mail. Once you have the script working, scheduling it is easy using cron.

I'm not as familiar with Powershell on Windows, but I bet if you search for "wget powershell" you would find some interesting results. I've heard scheduling Powershell scripts is similarly straightforward.

Answer 3

The best way to monitor the site is to do so from a source that simulates your users, so for a public facing site that means a monitor external to your organization (e.g., SiteUptime - random example, I've never used them nor do I know anything about their reputation). For an intranet application, I'm sure there are open source solutions you can deploy on the enterprise.

Your web server application may be running but because of a network or DNS issue, your users cannot reach it. It doesn't mean your application is down, but your users will not appreciate the distinction.

Answer 4

Well you can periodically ping a couple of sites, If non of them response for let's say 5 min. You are probably down.

Make sure to ping both local, country and continent located servers. In this way you can see if you have a LAN problem or a WAN problem and if it is worldwide (you are probably down) or if it is a backbone problem to certain parts of the world.

The second thing to think about is how reliable your DNS is. If the DNS is down, you will get nowhere. So to detect this, mix with both domain names and IP addresses.

To be able to mail yourself, you need of course a local Mail server (if your WAN is down).