In some cases, you would like to know when one of your tag disappears from some of your systems. It is possible to setup a monitor for such an alert scheme within Datadog:
- First, setup a classic metric monitor, and specify the metric and tag that you want to be alerted on
- Then, select some simple alert condition which should never be triggered, such as an alert over a very large value or under an impossible negative value
- Finally, activate the notify if data is missing option, as you can see on this example:
You should then be notified when the tag stops to be sent along with the chosen metric!