How we detect downtime

Here at Domain Monitor we have several different monitoring types as part of our monitoring suite of products.

Typically, to detect downtime for your website or API you'll configure your monitor using the HTTP method.

Put simply, this means that we'll send HTTP requests to your monitor's URL every X minutes based on your monitor's interval, and, each monitor configured can be specified with a monitor timeout which will be used as the maximum amount of time we'll wait for a response from your website.

Here's a summary of how downtime is detected for the HTTP monitor type:

• We send HTTP requests to your monitor URL every X minutes based on your monitor's interval/check frequency
• If no response is received within your timeout threshold then another request is instantly sent with the same timeout
• If both of these requests fail and receive no response, we send a third request with a timeout of 5 seconds just to finally confirm that it's down
  • Note: Keyword monitors will only run a maximum of two checks, the third check is omitted to reduce the number of requests going to potential third-party websites.
• If all three of these requests fail to receive a response then the monitor is marked as down if the monitor's HTTP status is anything other than a 2XX or 3XX status
• Then, when a monitor is down, we'll automatically send requests every minute for up-to 2 hours for faster uptime recovery. If the monitor is down for longer than 1 hour then the default monitor interval will be used until the monitor comes back online