There is unclear information about Alertmanager component configs. One section says that the config should be in a ConfigMap object and other section says that the secret config should be made in a secret resource, and not in a ConfigMap object.

See:

• "To configure core OpenShift Container Platform monitoring components, you must create the cluster-monitoring-config ConfigMap object in the openshift-monitoring project."
  • https://docs.openshift.com/container-platform/4.10/monitoring/configuring-the-monitoring-stack.html#creating-cluster-monitoring-configmap_configuring-the-monitoring-stack

• "The Alertmanager configuration is deployed as a secret resource in the openshift-monitoring namespace. If you have enabled a separate Alertmanager instance for user-defined alert routing, an Alertmanager configuration is also deployed as a secret resource in the openshift-user-workload-monitoring namespace. To configure additional routes for any instance of Alertmanager, you need to decode, modify, and then encode that secret. This procedure is a supported exception to the preceding statement."
  • https://docs.openshift.com/container-platform/4.11/monitoring/configuring-the-monitoring-stack.html#support-considerations_configuring-the-monitoring-stack

We need to clarify that the first sentence refers to the Cluster Monitoring Operator's configuration, which lives in the cluster-monitoring-config ConfigMap object and that the second sentence refers to the Alertmanager's configuration which lives either in the alertmanager-main secret (openshift-monitoring namespace) or in the alertmanager-user-workload secret (openshift-user-workload-monitoring namespace).

We should mention explicitly the names of the Alertmanager secrets in the documentation.