Document URL:
https://docs.openshift.com/container-platform/4.9/monitoring/configuring-the-monitoring-stack.html#setting-log-levels-for-monitoring-components_configuring-the-monitoring-stack

Section Number and Name:
Setting log levels for monitoring components

Describe the issue:
from 4.9, we could configure loglevel for alertmanager, see: https://issues.redhat.com/browse/MON-1661, but the doc does not mention it

Suggestions for improvement:
1. 
You can configure the log level for Prometheus Operator, Prometheus, Thanos Querier, and Thanos Ruler.
change to
You can configure the log level for Prometheus Operator, Prometheus, Thanos Querier, Alertmanager, and Thanos Ruler.

2.
Prerequisites section
If you are setting a log level for Prometheus Operator, Prometheus, or Thanos Querier in the openshift-monitoring project:
change to
If you are setting a log level for Prometheus Operator, Prometheus, Alertmanager, or Thanos Querier in the openshift-monitoring project:


Additional information:
apply for 4.9 and above versions