The host tag is assigned automatically by the Datadog Agent aggregating the metrics. Metrics submitted with a host tag not matching the Agent hostname lose reference to the original host. The submitted host tag overrides any hostname collected by or configured in the Agent.
Some metrics are sent with tags
service
,host
,path
,target
:https://github.com/fabiolb/fabio/blob/642e425cf664e23d257ca357b7b1bfd1e432683d/route/route.go#L64-L66
But
service
andhost
are reserved tag keys in DatadogAccording to Host tag
and https://github.com/DataDog/datadog-agent/issues/6245, these metric loose any configuration in the datadog-agent. In our case it is the
env
tag that is being lost.It can be tested with: