Prometheus Rules and Grafana Dashboards

Create Prometheus Rules and Grafana Dashboards on top of kube-prometheus

kube-prometheus ships with a set of default Prometheus rules and Grafana dashboards. At some point one might like to extend them, the purpose of this document is to explain how to do this.

All manifests of kube-prometheus are generated using jsonnet and Prometheus rules and Grafana dashboards in specific follow the Prometheus Monitoring Mixins proposal.

For both the Prometheus rules and the Grafana dashboards Kubernetes ConfigMaps are generated within kube-prometheus. In order to add additional rules and dashboards simply merge them onto the existing json objects. This document illustrates examples for rules as well as dashboards.

As a basis, all examples in this guide are based on the base example of the kube-prometheus readme:

local kp =
  (import 'kube-prometheus/main.libsonnet') +
  // Uncomment the following imports to enable its patches
  // (import 'kube-prometheus/addons/anti-affinity.libsonnet') +
  // (import 'kube-prometheus/addons/managed-cluster.libsonnet') +
  // (import 'kube-prometheus/addons/node-ports.libsonnet') +
  // (import 'kube-prometheus/addons/static-etcd.libsonnet') +
  // (import 'kube-prometheus/addons/custom-metrics.libsonnet') +
  // (import 'kube-prometheus/addons/external-metrics.libsonnet') +
  {
    values+:: {
      common+: {
        namespace: 'monitoring',
      },
    },
  };

{ 'setup/0namespace-namespace': kp.kubePrometheus.namespace } +
{
  ['setup/prometheus-operator-' + name]: kp.prometheusOperator[name]
  for name in std.filter((function(name) name != 'serviceMonitor' && name != 'prometheusRule'), std.objectFields(kp.prometheusOperator))
} +
// serviceMonitor and prometheusRule are separated so that they can be created after the CRDs are ready
{ 'prometheus-operator-serviceMonitor': kp.prometheusOperator.serviceMonitor } +
{ 'prometheus-operator-prometheusRule': kp.prometheusOperator.prometheusRule } +
{ 'kube-prometheus-prometheusRule': kp.kubePrometheus.prometheusRule } +
{ ['alertmanager-' + name]: kp.alertmanager[name] for name in std.objectFields(kp.alertmanager) } +
{ ['blackbox-exporter-' + name]: kp.blackboxExporter[name] for name in std.objectFields(kp.blackboxExporter) } +
{ ['grafana-' + name]: kp.grafana[name] for name in std.objectFields(kp.grafana) } +
{ ['kube-state-metrics-' + name]: kp.kubeStateMetrics[name] for name in std.objectFields(kp.kubeStateMetrics) } +
{ ['kubernetes-' + name]: kp.kubernetesControlPlane[name] for name in std.objectFields(kp.kubernetesControlPlane) }
{ ['node-exporter-' + name]: kp.nodeExporter[name] for name in std.objectFields(kp.nodeExporter) } +
{ ['prometheus-' + name]: kp.prometheus[name] for name in std.objectFields(kp.prometheus) } +
{ ['prometheus-adapter-' + name]: kp.prometheusAdapter[name] for name in std.objectFields(kp.prometheusAdapter) }

Prometheus rules

Alerting rules

According to the Prometheus Monitoring Mixins proposal Prometheus alerting rules are under the key prometheusAlerts in the top level object, so in order to add an additional alerting rule, we can simply merge an extra rule into the existing object.

The format is exactly the Prometheus format, so there should be no changes necessary should you have existing rules that you want to include.

Note that alerts can just as well be included into this file, using the jsonnet import function. In this example it is just inlined in order to demonstrate their use in a single file.

local kp = (import 'kube-prometheus/main.libsonnet') + {
  values+:: {
    common+: {
      namespace: 'monitoring',
    },
  },
  exampleApplication: {
    prometheusRuleExample: {
      apiVersion: 'monitoring.coreos.com/v1',
      kind: 'PrometheusRule',
      metadata: {
        name: 'my-prometheus-rule',
        namespace: $.values.common.namespace,
      },
      spec: {
        groups: [
          {
            name: 'example-group',
            rules: [
              {
                alert: 'ExampleAlert',
                expr: 'vector(1)',
                labels: {
                  severity: 'warning',
                },
                annotations: {
                  description: 'This is an example alert.',
                },
              },
            ],
          },
        ],
      },
    },
  },
};

{ ['00namespace-' + name]: kp.kubePrometheus[name] for name in std.objectFields(kp.kubePrometheus) } +
{ ['0prometheus-operator-' + name]: kp.prometheusOperator[name] for name in std.objectFields(kp.prometheusOperator) } +
{ ['node-exporter-' + name]: kp.nodeExporter[name] for name in std.objectFields(kp.nodeExporter) } +
{ ['kube-state-metrics-' + name]: kp.kubeStateMetrics[name] for name in std.objectFields(kp.kubeStateMetrics) } +
{ ['alertmanager-' + name]: kp.alertmanager[name] for name in std.objectFields(kp.alertmanager) } +
{ ['prometheus-' + name]: kp.prometheus[name] for name in std.objectFields(kp.prometheus) } +
{ ['prometheus-adapter-' + name]: kp.prometheusAdapter[name] for name in std.objectFields(kp.prometheusAdapter) } +
{ ['grafana-' + name]: kp.grafana[name] for name in std.objectFields(kp.grafana) } +
{ ['example-application-' + name]: kp.exampleApplication[name] for name in std.objectFields(kp.exampleApplication) }

Recording rules

In order to add a recording rule, simply do the same with the prometheusRules field.

Note that rules can just as well be included into this file, using the jsonnet import function. In this example it is just inlined in order to demonstrate their use in a single file.

local kp = (import 'kube-prometheus/main.libsonnet') + {
  values+:: {
    common+: {
      namespace: 'monitoring',
    },
  },
  exampleApplication: {
    prometheusRuleExample: {
      apiVersion: 'monitoring.coreos.com/v1',
      kind: 'PrometheusRule',
      metadata: {
        name: 'my-prometheus-rule',
        namespace: $.values.common.namespace,
      },
      spec: {
        groups: [
          {
            name: 'example-group',
            rules: [
              {
                record: 'some_recording_rule_name',
                expr: 'vector(1)',
              },
            ],
          },
        ],
      },
    },
  },
};

{ ['00namespace-' + name]: kp.kubePrometheus[name] for name in std.objectFields(kp.kubePrometheus) } +
{ ['0prometheus-operator-' + name]: kp.prometheusOperator[name] for name in std.objectFields(kp.prometheusOperator) } +
{ ['node-exporter-' + name]: kp.nodeExporter[name] for name in std.objectFields(kp.nodeExporter) } +
{ ['kube-state-metrics-' + name]: kp.kubeStateMetrics[name] for name in std.objectFields(kp.kubeStateMetrics) } +
{ ['alertmanager-' + name]: kp.alertmanager[name] for name in std.objectFields(kp.alertmanager) } +
{ ['prometheus-' + name]: kp.prometheus[name] for name in std.objectFields(kp.prometheus) } +
{ ['prometheus-adapter-' + name]: kp.prometheusAdapter[name] for name in std.objectFields(kp.prometheusAdapter) } +
{ ['grafana-' + name]: kp.grafana[name] for name in std.objectFields(kp.grafana) } +
{ ['example-application-' + name]: kp.exampleApplication[name] for name in std.objectFields(kp.exampleApplication) }

Pre-rendered rules

We acknowledge, that users may need to transition existing rules, and therefore allow an option to add additional pre-rendered rules. Luckily the yaml and json formats are very close so the yaml rules just need to be converted to json without any manual interaction needed. Just a tool to convert yaml to json is needed:

go get -u -v github.com/brancz/gojsontoyaml

And convert the existing rule file:

cat existingrule.yaml | gojsontoyaml -yamltojson > existingrule.json

Then import it in jsonnet:

local kp = (import 'kube-prometheus/main.libsonnet') + {
  values+:: {
    common+: {
      namespace: 'monitoring',
    },
  },
  exampleApplication: {
    prometheusRuleExample: {
      apiVersion: 'monitoring.coreos.com/v1',
      kind: 'PrometheusRule',
      metadata: {
        name: 'my-prometheus-rule',
        namespace: $.values.common.namespace,
      },
      spec: {
        groups: (import 'existingrule.json').groups,
      },
    },
  },
};

{ ['00namespace-' + name]: kp.kubePrometheus[name] for name in std.objectFields(kp.kubePrometheus) } +
{ ['0prometheus-operator-' + name]: kp.prometheusOperator[name] for name in std.objectFields(kp.prometheusOperator) } +
{ ['node-exporter-' + name]: kp.nodeExporter[name] for name in std.objectFields(kp.nodeExporter) } +
{ ['kube-state-metrics-' + name]: kp.kubeStateMetrics[name] for name in std.objectFields(kp.kubeStateMetrics) } +
{ ['alertmanager-' + name]: kp.alertmanager[name] for name in std.objectFields(kp.alertmanager) } +
{ ['prometheus-' + name]: kp.prometheus[name] for name in std.objectFields(kp.prometheus) } +
{ ['prometheus-adapter-' + name]: kp.prometheusAdapter[name] for name in std.objectFields(kp.prometheusAdapter) } +
{ ['grafana-' + name]: kp.grafana[name] for name in std.objectFields(kp.grafana) } +
{ ['example-application-' + name]: kp.exampleApplication[name] for name in std.objectFields(kp.exampleApplication) }

Changing default rules

Along with adding additional rules, we give the user the option to filter or adjust the existing rules imported by kube-prometheus/main.libsonnet. The recording rules can be found in kube-prometheus/components/mixin/rules and kubernetes-mixin/rules while the alerting rules can be found in kube-prometheus/components/mixin/alerts and kubernetes-mixin/alerts.

Knowing which rules to change, the user can now use functions from the Jsonnet standard library to make these changes. Below are examples of both a filter and an adjustment being made to the default rules. These changes can be assigned to a local variable and then added to the local kp object as seen in the examples above.

Filter

Here the alert KubeStatefulSetReplicasMismatch is being filtered out of the group kubernetes-apps. The default rule can be seen here. You first need to find out in which component the rule is defined (here it is kuberentesControlPlane).

local filter = {
  kubernetesControlPlane+: {
    prometheusRule+: {
      spec+: {
        groups: std.map(
          function(group)
            if group.name == 'kubernetes-apps' then
              group {
                rules: std.filter(
                  function(rule)
                    rule.alert != 'KubeStatefulSetReplicasMismatch',
                  group.rules
                ),
              }
            else
              group,
          super.groups
        ),
      },
    },
  },
};

Adjustment

Here the expression for another alert in the same component is updated from its previous value. The default rule can be seen here.

local update = {
  kubernetesControlPlane+: {
    prometheusRule+: {
      spec+: {
        groups: std.map(
          function(group)
            if group.name == 'kubernetes-apps' then
              group {
                rules: std.map(
                  function(rule)
                    if rule.alert == 'KubePodCrashLooping' then
                      rule {
                        expr: 'rate(kube_pod_container_status_restarts_total{namespace=kube-system,job="kube-state-metrics"}[10m]) * 60 * 5 > 0',
                      }
                    else
                      rule,
                  group.rules
                ),
              }
            else
              group,
          super.groups
        ),
      },
    },
  },
};

Using the example from above about adding in pre-rendered rules, the new local variables can be added in as follows:

local add = {
  exampleApplication:: {
    prometheusRule+: {
      apiVersion: 'monitoring.coreos.com/v1',
      kind: 'PrometheusRule',
      metadata: {
        name: 'example-application-rules',
        namespace: $.values.common.namespace,
      },
      spec: (import 'existingrule.json'),
    },
  },
};
local kp = (import 'kube-prometheus/main.libsonnet') + filter + update + add;
local kp = (import 'kube-prometheus/main.libsonnet') +
            filter +
            update +
            add + {
	      values+:: {
                common+: {
                  namespace: 'monitoring',
                },
              },
            };
{ 'setup/0namespace-namespace': kp.kubePrometheus.namespace } +
{
  ['setup/prometheus-operator-' + name]: kp.prometheusOperator[name]
  for name in std.filter((function(name) name != 'serviceMonitor' && name != 'prometheusRule'), std.objectFields(kp.prometheusOperator))
} +
// serviceMonitor and prometheusRule are separated so that they can be created after the CRDs are ready
{ 'prometheus-operator-serviceMonitor': kp.prometheusOperator.serviceMonitor } +
{ 'prometheus-operator-prometheusRule': kp.prometheusOperator.prometheusRule } +
{ 'kube-prometheus-prometheusRule': kp.kubePrometheus.prometheusRule } +
{ ['node-exporter-' + name]: kp.nodeExporter[name] for name in std.objectFields(kp.nodeExporter) } +
{ ['blackbox-exporter-' + name]: kp.blackboxExporter[name] for name in std.objectFields(kp.blackboxExporter) } +
{ ['kube-state-metrics-' + name]: kp.kubeStateMetrics[name] for name in std.objectFields(kp.kubeStateMetrics) } +
{ ['alertmanager-' + name]: kp.alertmanager[name] for name in std.objectFields(kp.alertmanager) } +
{ ['prometheus-' + name]: kp.prometheus[name] for name in std.objectFields(kp.prometheus) } +
{ ['prometheus-adapter-' + name]: kp.prometheusAdapter[name] for name in std.objectFields(kp.prometheusAdapter) } +
{ ['grafana-' + name]: kp.grafana[name] for name in std.objectFields(kp.grafana) } +
{ ['kubernetes-' + name]: kp.kubernetesControlPlane[name] for name in std.objectFields(kp.kubernetesControlPlane) } +
{ ['exampleApplication-' + name]: kp.exampleApplication[name] for name in std.objectFields(kp.exampleApplication) }

Dashboards

Dashboards can either be added using jsonnet or simply a pre-rendered json dashboard.

Jsonnet dashboard

We recommend using the grafonnet library for jsonnet, which gives you a simple DSL to generate Grafana dashboards. Following the Prometheus Monitoring Mixins proposal additional dashboards are added to the grafanaDashboards key, located in the top level object. To add new jsonnet dashboards, simply add one.

Note that dashboards can just as well be included into this file, using the jsonnet import function. In this example it is just inlined in order to demonstrate their use in a single file.

local grafana = import 'grafonnet/grafana.libsonnet';
local dashboard = grafana.dashboard;
local row = grafana.row;
local prometheus = grafana.prometheus;
local template = grafana.template;
local graphPanel = grafana.graphPanel;

local kp = (import 'kube-prometheus/main.libsonnet') + {
  values+:: {
    common+:: {
      namespace: 'monitoring',
    },
    grafana+: {
      dashboards+:: {
        'my-dashboard.json':
          dashboard.new('My Dashboard')
          .addTemplate(
            {
              current: {
                text: 'Prometheus',
                value: 'Prometheus',
              },
              hide: 0,
              label: null,
              name: 'datasource',
              options: [],
              query: 'prometheus',
              refresh: 1,
              regex: '',
              type: 'datasource',
            },
          )
          .addRow(
            row.new()
            .addPanel(graphPanel.new('My Panel', span=6, datasource='$datasource')
                      .addTarget(prometheus.target('vector(1)')))
          ),
      },
    },
  },
};

{ ['00namespace-' + name]: kp.kubePrometheus[name] for name in std.objectFields(kp.kubePrometheus) } +
{ ['0prometheus-operator-' + name]: kp.prometheusOperator[name] for name in std.objectFields(kp.prometheusOperator) } +
{ ['node-exporter-' + name]: kp.nodeExporter[name] for name in std.objectFields(kp.nodeExporter) } +
{ ['kube-state-metrics-' + name]: kp.kubeStateMetrics[name] for name in std.objectFields(kp.kubeStateMetrics) } +
{ ['alertmanager-' + name]: kp.alertmanager[name] for name in std.objectFields(kp.alertmanager) } +
{ ['prometheus-' + name]: kp.prometheus[name] for name in std.objectFields(kp.prometheus) } +
{ ['grafana-' + name]: kp.grafana[name] for name in std.objectFields(kp.grafana) }

Pre-rendered Grafana dashboards

As jsonnet is a superset of json, the jsonnet import function can be used to include Grafana dashboard json blobs. In this example we are importing a provided example dashboard.

local kp = (import 'kube-prometheus/main.libsonnet') + {
  values+:: {
    common+:: {
      namespace: 'monitoring',
    },
    grafana+: {
      dashboards+:: {  // use this method to import your dashboards to Grafana
        'my-dashboard.json': (import 'example-grafana-dashboard.json'),
      },
    },
  },
};

{ ['00namespace-' + name]: kp.kubePrometheus[name] for name in std.objectFields(kp.kubePrometheus) } +
{ ['0prometheus-operator-' + name]: kp.prometheusOperator[name] for name in std.objectFields(kp.prometheusOperator) } +
{ ['node-exporter-' + name]: kp.nodeExporter[name] for name in std.objectFields(kp.nodeExporter) } +
{ ['kube-state-metrics-' + name]: kp.kubeStateMetrics[name] for name in std.objectFields(kp.kubeStateMetrics) } +
{ ['alertmanager-' + name]: kp.alertmanager[name] for name in std.objectFields(kp.alertmanager) } +
{ ['prometheus-' + name]: kp.prometheus[name] for name in std.objectFields(kp.prometheus) } +
{ ['grafana-' + name]: kp.grafana[name] for name in std.objectFields(kp.grafana) }

In case you have lots of json dashboard exported out from grafana UI the above approach is going to take lots of time to improve performance we can use rawDashboards field and provide it’s value as json string by using importstr

local kp = (import 'kube-prometheus/main.libsonnet') + {
  values+:: {
    common+:: {
      namespace: 'monitoring',
    },
    grafana+: {
      rawDashboards+:: {
        'my-dashboard.json': (importstr 'example-grafana-dashboard.json'),
      },
    },
  },
};

{ ['00namespace-' + name]: kp.kubePrometheus[name] for name in std.objectFields(kp.kubePrometheus) } +
{ ['0prometheus-operator-' + name]: kp.prometheusOperator[name] for name in std.objectFields(kp.prometheusOperator) } +
{ ['node-exporter-' + name]: kp.nodeExporter[name] for name in std.objectFields(kp.nodeExporter) } +
{ ['kube-state-metrics-' + name]: kp.kubeStateMetrics[name] for name in std.objectFields(kp.kubeStateMetrics) } +
{ ['alertmanager-' + name]: kp.alertmanager[name] for name in std.objectFields(kp.alertmanager) } +
{ ['prometheus-' + name]: kp.prometheus[name] for name in std.objectFields(kp.prometheus) } +
{ ['grafana-' + name]: kp.grafana[name] for name in std.objectFields(kp.grafana) }

Mixins

Kube-prometheus comes with a couple of default mixins as the Kubernetes-mixin and the Node-exporter mixin, however there are many more mixins. To use other mixins Kube-prometheus has a jsonnet library for creating a Kubernetes PrometheusRule CRD and Grafana dashboards from a mixin. Below is an example of creating a mixin object that has Prometheus rules and Grafana dashboards:

// Import the library function for adding mixins
local addMixin = (import 'kube-prometheus/lib/mixin.libsonnet');

// Create your mixin
local myMixin = addMixin({
  name: 'myMixin',
  mixin: import 'my-mixin/mixin.libsonnet',
});

The myMixin object will have two objects - prometheusRules and grafanaDashboards. The grafanaDashboards object will be needed to be added to the dashboards field as in the example below:

values+:: {
  grafana+:: {
    dashboards+:: myMixin.grafanaDashboards

The prometheusRules object is a PrometheusRule Kubernetes CRD and it should be defined as its own jsonnet object. If you define multiple mixins in a single jsonnet object there is a possibility that they will overwrite each others' configuration and there will be unintended effects. Therefore, use the prometheusRules object as its own jsonnet object:

...
{ ['kubernetes-' + name]: kp.kubernetesControlPlane[name] for name in std.objectFields(kp.kubernetesControlPlane) }
{ ['node-exporter-' + name]: kp.nodeExporter[name] for name in std.objectFields(kp.nodeExporter) } +
{ ['prometheus-' + name]: kp.prometheus[name] for name in std.objectFields(kp.prometheus) } +
{ 'external-mixins/my-mixin-prometheus-rules': myMixin.prometheusRules } // one object for each mixin

As mentioned above each mixin is configurable and you would configure the mixin as in the example below:

local myMixin = addMixin({
  name: 'myMixin',
  mixin: (import 'my-mixin/mixin.libsonnet') + {
    _config+:: {
      myMixinSelector: 'my-selector',
      interval: '30d', // example
    },
  },
});

The library has also two optional parameters - the namespace for the PrometheusRule CRD and the dashboard folder for the Grafana dashboards. The below example shows how to use both:

local myMixin = addMixin({
  name: 'myMixin',
  namespace: 'prometheus', // default is monitoring
  dashboardFolder: 'Observability',
  mixin: (import 'my-mixin/mixin.libsonnet') + {
    _config+:: {
      myMixinSelector: 'my-selector',
      interval: '30d', // example
    },
  },
});

The created prometheusRules object will have the metadata field namespace added and the usage will remain the same. However, the grafanaDasboards will be added to the folderDashboards field instead of the dashboards field as shown in the example below:

values+:: {
  grafana+:: {
    folderDashboards+:: {
        Kubernetes: {
            ...
        },
        Misc: {
            'grafana-home.json': import 'dashboards/misc/grafana-home.json',
        },
    } + myMixin.grafanaDashboards

Full example of including etcd mixin using method described above:

local addMixin = (import 'kube-prometheus/lib/mixin.libsonnet');
local etcdMixin = addMixin({
  name: 'etcd',
  mixin: (import 'github.com/etcd-io/etcd/contrib/mixin/mixin.libsonnet') + {
    _config+: {},  // mixin configuration object
  },
});

local kp = (import 'kube-prometheus/main.libsonnet') +
           {
             values+:: {
               common+: {
                 namespace: 'monitoring',
               },
               grafana+: {
                 // Adding new dashboard to grafana. This will modify grafana configMap with dashboards
                 dashboards+: etcdMixin.grafanaDashboards,
               },
             },
           };

{ ['00namespace-' + name]: kp.kubePrometheus[name] for name in std.objectFields(kp.kubePrometheus) } +
{ ['0prometheus-operator-' + name]: kp.prometheusOperator[name] for name in std.objectFields(kp.prometheusOperator) } +
{ ['node-exporter-' + name]: kp.nodeExporter[name] for name in std.objectFields(kp.nodeExporter) } +
{ ['kube-state-metrics-' + name]: kp.kubeStateMetrics[name] for name in std.objectFields(kp.kubeStateMetrics) } +
{ ['alertmanager-' + name]: kp.alertmanager[name] for name in std.objectFields(kp.alertmanager) } +
{ ['prometheus-' + name]: kp.prometheus[name] for name in std.objectFields(kp.prometheus) } +
{ ['grafana-' + name]: kp.grafana[name] for name in std.objectFields(kp.grafana) } +
// Rendering prometheusRules object. This is an object compatible with prometheus-operator CRD definition for prometheusRule
{ 'external-mixins/etcd-mixin-prometheus-rules': etcdMixin.prometheusRules }