Prometheus service stop alert

Question

I have configured alert manager to send me an email when an instance is down like the following

groups:
- name: Down
  rules:
  - alert: InstanceDown
    expr: up == 0
    for: 3m
    labels:
      severity: 'critical'
    annotations:
      summary: "Instance  is down"
      description: " of job  has been down for more than 3 minutes."

but I want to add another role for node-exporter service stop, how can I do that?

Answer 1

Could you clarify your question a bit?

The up == 0 expression will fire an alert for each target Prometheus is unable to scrape. The node exporter is a target and should trigger that alert.

Try to stop the node exporter service, and check Prometheus for a pending alert.