Move metrics docs to getting-started sections

Author: rsienko

docs/getting-started/helm-installation.md

@@ -30,6 +30,9 @@ sharedIPLoadBalancing:
   loadBalancerType: cilium-bgp
   bgpNodeSelector: cilium-bgp-peering=true
   ipHolderSuffix: ""
+
+# Optional: Allow /metrics scraping without authorization on secure HTTPS port (10253 by default)
+allowUnauthorizedMetrics=true
 ```
 
 3. Install the CCM:

docs/getting-started/manual-installation.md

@@ -48,6 +48,16 @@ resources:
     memory: 256Mi
 ```
 
+### Prometheus metrics
+
+Cloud Controller Manager exposes metrics by default on port given by
+`--secure-port` flag. The endpoint is protected from unauthenticated access by
+default. To allow unauthenticated clients (`system:anonymous`) access
+Prometheus metrics, use `--authorization-always-allow-paths="/metrics"`
+command-line flag.
+
+Linode API calls can be monitored using `ccm_linode_client_requests_total` metric.
+
 ## Uninstalling
 
 To remove the CCM: