Enable Multi Cluster alerts by default (#2099)

jsonnet/kube-prometheus/components/k8s-control-plane.libsonnet

@@ -11,6 +11,7 @@ local defaults = {
   mixin:: {
     ruleLabels: {},
     _config: {
+      showMultiCluster: true,
       cadvisorSelector: 'job="kubelet", metrics_path="/metrics/cadvisor"',
       kubeletSelector: 'job="kubelet", metrics_path="/metrics"',
       kubeStateMetricsSelector: 'job="kube-state-metrics"',

jsonnet/kube-prometheus/components/mixin/alerts/general.libsonnet

@@ -10,7 +10,7 @@
               summary: 'One or more targets are unreachable.',
               description: '{{ printf "%.4g" $value }}% of the {{ $labels.job }}/{{ $labels.service }} targets in {{ $labels.namespace }} namespace are down.',
             },
-            expr: '100 * (count(up == 0) BY (job, namespace, service) / count(up) BY (job, namespace, service)) > 10',
+            expr: '100 * (count(up == 0) BY (cluster, job, namespace, service) / count(up) BY (cluster, job, namespace, service)) > 10',
             'for': '10m',
             labels: {
               severity: 'warning',

jsonnet/kube-prometheus/components/prometheus-operator.libsonnet

@@ -38,6 +38,7 @@ local defaults = {
       prometheus: defaults.name,
     },
     _config: {
+      groupLabels: 'cluster,controller,namespace',
       prometheusOperatorSelector: 'job="prometheus-operator",namespace="' + defaults.namespace + '"',
       runbookURLPattern: 'https://runbooks.prometheus-operator.dev/runbooks/prometheus-operator/%s',
     },