Monitoring & Metrics

Cilium and Hubble can both be configured to serve Prometheus metrics. Prometheus is a pluggable metrics collection and storage system and can act as a data source for Grafana, a metrics visualization frontend. Unlike some metrics collectors like statsd, Prometheus requires the collectors to pull metrics from each source.

Cilium and Hubble metrics can be enabled independently of each other.

Cilium Metrics

Cilium metrics provide insights into the state of Cilium itself, namely of the cilium-agent, cilium-envoy, and cilium-operator processes. To run Cilium with Prometheus metrics enabled, deploy it with the prometheus.enabled=true Helm value set.

Cilium metrics are exported under the cilium_ Prometheus namespace. Envoy metrics are exported under the envoy_ Prometheus namespace, of which the Cilium-defined metrics are exported under the envoy_cilium_ namespace. When running and collecting in Kubernetes they will be tagged with a pod name and namespace.

Installation

You can enable metrics for cilium-agent (including Envoy) with the Helm value prometheus.enabled=true. To enable metrics for cilium-operator, use operator.prometheus.enabled=true.

helm install cilium cilium/cilium --version 1.10.2 \
  --namespace kube-system \
  --set prometheus.enabled=true \
  --set operator.prometheus.enabled=true

The ports can be configured via prometheus.port, proxy.prometheus.port, or operator.prometheus.port respectively.

When metrics are enabled, all Cilium components will have the following annotations. They can be used to signal Prometheus whether to scrape metrics:

prometheus.io/scrape: true
prometheus.io/port: 9090

To collect Envoy metrics the Cilium chart will create a Kubernetes headless service named cilium-agent with the prometheus.io/scrape:'true' annotation set:

prometheus.io/scrape: true
prometheus.io/port: 9095

This additional headless service in addition to the other Cilium components is needed as each component can only have one Prometheus scrape and port annotation.

Prometheus will pick up the Cilium and Envoy metrics automatically if the following option is set in the scrape_configs section:

scrape_configs:
- job_name: 'kubernetes-pods'
  kubernetes_sd_configs:
  - role: pod
  relabel_configs:
    - source_labels: [__meta_kubernetes_pod_annotation_prometheus_io_scrape]
      action: keep
      regex: true
    - source_labels: [__address__, __meta_kubernetes_pod_annotation_prometheus_io_port]
      action: replace
      regex: (.+):(?:\d+);(\d+)
      replacement: ${1}:${2}
      target_label: __address__

Hubble Metrics

While Cilium metrics allow you to monitor the state Cilium itself, Hubble metrics on the other hand allow you to monitor the network behavior of your Cilium-managed Kubernetes pods with respect to connectivity and security.

Installation

To deploy Cilium with Hubble metrics enabled, you need to enable Hubble with hubble.enabled=true and provide a set of Hubble metrics you want to enable via hubble.metrics.enabled.

Some of the metrics can also be configured with additional options. See the Hubble exported metrics section for the full list of available metrics and their options.

helm install cilium cilium/cilium --version 1.10.2 \
  --namespace kube-system \
  --set hubble.metrics.enabled="{dns,drop,tcp,flow,icmp,http}"

The port of the Hubble metrics can be configured with the hubble.metrics.port Helm value.

Note

L7 metrics such as HTTP, are only emitted for pods that enable Layer 7 Protocol Visibility.

When deployed with a non-empty hubble.metrics.enabled Helm value, the Cilium chart will create a Kubernetes headless service named hubble-metrics with the prometheus.io/scrape:'true' annotation set:

prometheus.io/scrape: true
prometheus.io/port: 9091

Set the following options in the scrape_configs section of Prometheus to have it scrape all Hubble metrics from the endpoints automatically:

scrape_configs:
  - job_name: 'kubernetes-endpoints'
    scrape_interval: 30s
    kubernetes_sd_configs:
      - role: endpoints
    relabel_configs:
      - source_labels: [__meta_kubernetes_service_annotation_prometheus_io_scrape]
        action: keep
        regex: true
      - source_labels: [__address__, __meta_kubernetes_service_annotation_prometheus_io_port]
        action: replace
        target_label: __address__
        regex: (.+)(?::\d+);(\d+)
        replacement: $1:$2

Example Prometheus & Grafana Deployment

If you don’t have an existing Prometheus and Grafana stack running, you can deploy a stack with:

kubectl apply -f https://raw.githubusercontent.com/cilium/cilium/v1.10/examples/kubernetes/addons/prometheus/monitoring-example.yaml

It will run Prometheus and Grafana in the cilium-monitoring namespace. If you have either enabled Cilium or Hubble metrics, they will automatically be scraped by Prometheus. You can then expose Grafana to access it via your browser.

kubectl -n cilium-monitoring port-forward service/grafana --address 0.0.0.0 --address :: 3000:3000

Open your browser and access http://localhost:3000/

Metrics Reference

cilium-agent

Configuration

To expose any metrics, invoke cilium-agent with the --prometheus-serve-addr option. This option takes a IP:Port pair but passing an empty IP (e.g. :9090) will bind the server to all available interfaces (there is usually only one in a container).

Exported Metrics

Endpoint

Services

Cluster health

Datapath

eBPF

Both bpf_maps_virtual_memory_max_bytes and bpf_progs_virtual_memory_max_bytes are currently reporting the system-wide memory usage of eBPF that is directly and not directly managed by Cilium. This might change in the future and only report the eBPF memory usage directly managed by Cilium.

Drops/Forwards (L3/L4)

Policy

Policy L7 (HTTP/Kafka)

Identity

Events external to Cilium

Controllers

SubProcess

Kubernetes

IPAM

KVstore

Agent

FQDN

API Rate Limiting

cilium-operator

Configuration

cilium-operator can be configured to serve metrics by running with the option --enable-metrics. By default, the operator will expose metrics on port 6942, the port can be changed with the option --operator-prometheus-serve-addr.

Exported Metrics

All metrics are exported under the cilium_operator_ Prometheus namespace.

IPAM

Hubble

Configuration

Hubble metrics are served by a Hubble instance running inside cilium-agent. The command-line options to configure them are --enable-hubble, --hubble-metrics-server, and --hubble-metrics. --hubble-metrics-server takes an IP:Port pair, but passing an empty IP (e.g. :9091) will bind the server to all available interfaces. --hubble-metrics takes a comma-separated list of metrics.

Some metrics can take additional semicolon-separated options per metric, e.g. --hubble-metrics="dns:query;ignoreAAAA,http:destinationContext=pod-short" will enable the dns metric with the query and ignoreAAAA options, and the http metric with the destinationContext=pod-short option.

Context Options

Most Hubble metrics can be configured to add the source and/or destination context as a label. The options are called sourceContext and destinationContext. The possible values are:

When specifying the source and/or destination context, multiple contexts can be specified by separating them via the | symbol. When multiple are specified, then the first non-empty value is added to the metric as a label. For example, a metric configuration of flow:destinationContext=dns|ip will first try to use the DNS name of the target for the label. If no DNS name is known for the target, it will fall back and use the IP address of the target instead.

Exported Metrics

Hubble metrics are exported under the hubble_ Prometheus namespace.

dns

Options

This metric supports Context Options.

drop

Options

This metric supports Context Options.

flow

Options

This metric supports Context Options.

http

Options

This metric supports Context Options.

icmp

Options

This metric supports Context Options.

port-distribution

Options

This metric supports Context Options.

tcp

Options

This metric supports Context Options.