Adding Prometheus Alertmanager in Grafana

Version of Grafana : v9.0.0

Hi, I’m trying to add a prometheus alert manager instance into Grafana as a datasource. If I perform this from the UI, it works.

So, I now try to add this in the datasource.yaml which is mounted into my Grafana container as a configmap.

/etc/grafana/provisioning/datasources $ cat datasources.yaml
apiVersion: 1
- isDefault: true
  name: Prometheus
  type: prometheus
  url: http://prometheus-operated:9090
- name: Alertmanager
  access: proxy
  implementation: prometheus
  type: alertmanager
  url: http://alertmanager-operated:9093

Note - I had to define the implementation type as prometheus as the default is to use Cortex.

Now, having loaded this, when I check in the UI, I receive this message.

For some reason, implementation is ignored, yet even changing this manually to Prometheus still results in the same error.

I’m hoping there is something obvious to this but I can’t find anything obvious.