Make custom metrics endpoint configurable to be adapted to edge environments

charts/azuremonitor-containers/templates/omsagent-daemonset.yaml

@@ -103,6 +103,14 @@ spec:
        {{- end }}
        - name: ISTEST
          value: {{ .Values.omsagent.ISTEST | quote }}
+       {{ if .Values.omsagent.isArcACluster }}
+       - name: IS_ARCA_CLUSTER
+         value: {{ .Values.omsagent.isArcACluster | quote }}
+       {{- end }}
+       {{- if ne .Values.omsagent.metricsEndpoint "<your_metrics_endpoint>" }}
+       - name: CUSTOM_METRICS_ENDPOINT
+         value: {{ .Values.omsagent.metricsEndpoint | quote }}
+       {{- end }}
        securityContext:
          privileged: true
        ports:

charts/azuremonitor-containers/templates/omsagent-deployment.yaml

@@ -89,6 +89,14 @@ spec:
          value: {{ .Values.omsagent.sidecarscraping | quote }}
        - name: ISTEST
          value: {{ .Values.omsagent.ISTEST | quote }}
+       {{ if .Values.omsagent.isArcACluster }}
+       - name: IS_ARCA_CLUSTER
+         value: {{ .Values.omsagent.isArcACluster | quote }}
+       {{- end }}
+       {{- if ne .Values.omsagent.metricsEndpoint "<your_metrics_endpoint>" }}
+       - name: CUSTOM_METRICS_ENDPOINT
+         value: {{ .Values.omsagent.metricsEndpoint | quote }}
+       {{- end }}
        securityContext:
          privileged: true
        ports:

charts/azuremonitor-containers/values.yaml

@@ -49,6 +49,9 @@ omsagent:
   # This flag used to determine whether to use AAD MSI auth or not for Arc K8s cluster
   useAADAuth: false
 
+  # This flag used to determine whether this cluster is connected to ArcA control plane. This value will be setup before pushed into on-premise ArcA ACR.
+  isArcACluster: false
+
   ## To get your workspace id and key do the following
   ## You can create a Azure Loganalytics workspace from portal.azure.com and get its ID & PRIMARY KEY from 'Advanced Settings' tab in the Ux.
 
@@ -57,6 +60,8 @@ omsagent:
     key: <your_workspace_key>
   domain: opinsights.azure.com
   proxy: <your_proxy_config>
+  # This metricsEndpoint used to define the endpoint custom metrics emit to. If not defined, default public Azure monitoring endpoint '{aks_region}.monitoring.azure.com' will be used.
+  metricsEndpoint: <your_metrics_endpoint>
   env:
     clusterName: <your_cluster_name>
     ## Applicable for only managed clusters hosted in Azure

source/plugins/ruby/CustomMetricsUtils.rb

@@ -13,6 +13,11 @@ def check_custom_metrics_availability
             if aks_region.to_s.empty? || aks_resource_id.to_s.empty?
                 return false # This will also take care of AKS-Engine Scenario. AKS_REGION/AKS_RESOURCE_ID is not set for AKS-Engine. Only ACS_RESOURCE_NAME is set
             end
+            # If this is cluster is connected to ArcA control plane and metrics endpoint provided, custom metrics shall be emitted.
+            is_arca_cluster = ENV['IS_ARCA_CLUSTER']
+            if is_arca_cluster.to_s.downcase == "true" && !ENV['CUSTOM_METRICS_ENDPOINT'].to_s.empty?
+                return true
+            end
 
             return aks_cloud_environment.to_s.downcase == 'azurepubliccloud'
         end

source/plugins/ruby/out_mdm.rb

@@ -26,7 +26,8 @@ def initialize
       @@token_resource_audience = "https://monitor.azure.com/"
       @@grant_type = "client_credentials"
       @@azure_json_path = "/etc/kubernetes/host/azure.json"
-      @@post_request_url_template = "https://%{aks_region}.monitoring.azure.com%{aks_resource_id}/metrics"
+      @@public_metrics_endpoint_template = "https://%{aks_region}.monitoring.azure.com"
+      @@post_request_url_template = "%{metrics_endpoint}%{aks_resource_id}/metrics"
       @@aad_token_url_template = "https://login.microsoftonline.com/%{tenant_id}/oauth2/token"
 
       # msiEndpoint is the well known endpoint for getting MSI authentications tokens
@@ -98,7 +99,16 @@ def start
           if aks_resource_id.downcase.include?("microsoft.kubernetes/connectedclusters")
             @isArcK8sCluster = true
           end
-          @@post_request_url = @@post_request_url_template % { aks_region: aks_region, aks_resource_id: aks_resource_id }
+
+          # If CUSTOM_METRICS_ENDPOINT provided, the url format shall be validated before emitting metrics into given endpoint.
+          custom_metrics_endpoint = ENV['CUSTOM_METRICS_ENDPOINT']
+          if !custom_metrics_endpoint.to_s.empty?
+            metrics_endpoint = custom_metrics_endpoint.strip
+            URI.parse(metrics_endpoint)
+          else
+            metrics_endpoint = @@public_metrics_endpoint_template % { aks_region: aks_region }
+          end
+          @@post_request_url = @@post_request_url_template % { metrics_endpoint: metrics_endpoint, aks_resource_id: aks_resource_id }
           @post_request_uri = URI.parse(@@post_request_url)
           proxy = (ProxyUtils.getProxyConfiguration)
           if proxy.nil? || proxy.empty?