mgr/dashboard: extend dashboard documentation

by adding the previously added monitoring related features as well as
the newest feature addition. Extends the documentation where necessary
to describe the Prometheus' alert configuration.

Fixes: https://tracker.ceph.com/issues/42877
Signed-off-by: Patrick Seidensal <pseidensal@suse.com>
(cherry picked from commit 36421284c315baf7e79a8c0586ca98ac0126037e)

diff --git a/doc/mgr/dashboard.rst b/doc/mgr/dashboard.rst
index 26c95ca0316eec209fbb9bb750e156240848e1b4..b6bcb91a295362ac26b6bfee7eee8d06fba2b3dd 100644 (file)
--- a/doc/mgr/dashboard.rst
+++ b/doc/mgr/dashboard.rst
@@ -73,6 +73,10 @@ aspects of your Ceph cluster:
 * **Performance counters**: Display detailed service-specific statistics for
   each running service.
 * **Monitors**: List all MONs, their quorum status, open sessions.
+* **Monitoring**: Enables creation, re-creation, editing and expiration of
+  Prometheus' Silences, lists the alerting configuration of Prometheus and
+  currently firing alerts. Also shows notifications for firing alerts. Needs
+  configuration.
 * **Configuration Editor**: Display all available configuration options,
   their description, type and default values and edit the current values.
 * **Pools**: List all Ceph pools and their details (e.g. applications,
@@ -534,9 +538,9 @@ in order to manage silences.
 
 #. Use the API of Prometheus and the Alertmanager
 
-   This allows you to manage alerts and silences. You will see all alerts and silences
-   the Alertmanager currently knows of in the corresponding listing.
-   Both can be found in the *Cluster* submenu.
+   This allows you to manage alerts and silences. This will enable the "Active
+   Alerts", "All Alerts" as well as the "Silences" tabs in the "Monitoring"
+   section of the "Cluster" menu entry.
 
    Alerts can be sorted by name, job, severity, state and start time.
    Unfortunately it's not possible to know when an alert
@@ -563,8 +567,11 @@ in order to manage silences.
 
      $ ceph dashboard set-alertmanager-api-host 'http://localhost:9093'
 
-   To be able to show what a silence will match beforehand, you have to add the host
-   and port of the Prometheus server::
+   To be able to see all configured alerts, you will need to configure the URL
+   to the Prometheus API. Using this API, the UI will also help you in verifying
+   that a new silence will match a corresponding alert.
+
+   ::
 
      $ ceph dashboard set-prometheus-api-host <prometheus-host:port>  # default: ''
 
@@ -572,7 +579,7 @@ in order to manage silences.
 
      $ ceph dashboard set-prometheus-api-host 'http://localhost:9090'
 
-   After setting up the hosts, you have to refresh your the dashboard in your browser window.
+   After setting up the hosts, you have to refresh the dashboard in your browser window.
 
 #. Use both methods