Merge pull request #266306 from aritraghosh/patch-11

Update monitor-control-plane-metrics.md

Author: prmerger-automator[bot]

articles/aks/monitor-control-plane-metrics.md

@@ -195,6 +195,15 @@ When you enable the add-on, you might have specified an existing workspace that
 
 You can disable control plane metrics at any time, by either disabling the feature flag, disabling managed Prometheus, or by deleting the AKS cluster.
 
+## Preview flag enabled after Managed Prometheus setup
+If the preview flag(`AzureMonitorMetricsControlPlanePreview`) was enabled on an existing Managed Prometheus cluster, it will require forcing an update for the cluster to emit control plane metrics
+
+You can run an az aks update to ensure the cluster updates to start collecting control plane metrics.
+
+```azurecli
+az aks update -n <cluster-name> -g <resource-group>
+```
+
 > [!NOTE]
 > This action doesn't remove any existing data stored in your Azure Monitor workspace.