traefik/docs/content/observability/metrics/prometheus.md

title	description
Traefik Prometheus Documentation	Traefik supports several metrics backends, including Prometheus. Learn how to implement it for observability in Traefik Proxy. Read the technical documentation.

Prometheus

To enable the Prometheus:

metrics:
  prometheus: {}

[metrics]
  [metrics.prometheus]

--metrics.prometheus=true

buckets

Optional, Default="0.100000, 0.300000, 1.200000, 5.000000"

Buckets for latency metrics.

metrics:
  prometheus:
    buckets:
      - 0.1
      - 0.3
      - 1.2
      - 5.0

[metrics]
  [metrics.prometheus]
    buckets = [0.1,0.3,1.2,5.0]

--metrics.prometheus.buckets=0.1,0.3,1.2,5.0

addEntryPointsLabels

Optional, Default=true

Enable metrics on entry points.

metrics:
  prometheus:
    addEntryPointsLabels: true

[metrics]
  [metrics.prometheus]
    addEntryPointsLabels = true

--metrics.prometheus.addEntryPointsLabels=true

addRoutersLabels

Optional, Default=false

Enable metrics on routers.

metrics:
  prometheus:
    addRoutersLabels: true

[metrics]
  [metrics.prometheus]
    addRoutersLabels = true

--metrics.prometheus.addrouterslabels=true

addServicesLabels

Optional, Default=true

Enable metrics on services.

metrics:
  prometheus:
    addServicesLabels: true

[metrics]
  [metrics.prometheus]
    addServicesLabels = true

--metrics.prometheus.addServicesLabels=true

entryPoint

Optional, Default=traefik

Entry point used to expose metrics.

entryPoints:
  metrics:
    address: :8082

metrics:
  prometheus:
    entryPoint: metrics

[entryPoints]
  [entryPoints.metrics]
    address = ":8082"

[metrics]
  [metrics.prometheus]
    entryPoint = "metrics"

--entryPoints.metrics.address=:8082
--metrics.prometheus.entryPoint=metrics

manualRouting

Optional, Default=false

If manualRouting is true, it disables the default internal router in order to allow one to create a custom router for the prometheus@internal service.

metrics:
  prometheus:
    manualRouting: true

[metrics]
  [metrics.prometheus]
    manualRouting = true

--metrics.prometheus.manualrouting=true

headerLabels

Optional

Defines the extra labels for the requests_total metrics, and for each of them, the request header containing the value for this label. Please note that if the header is not present in the request it will be added nonetheless with an empty value. In addition, the label should be a valid label name for Prometheus metrics, otherwise, the Prometheus metrics provider will fail to serve any Traefik-related metric.

metrics:
  prometheus:
    headerLabels:
      label: headerKey

[metrics]
  [metrics.prometheus]
    [metrics.prometheus.headerLabels]
      label = "headerKey"

--metrics.prometheus.headerlabels.label=headerKey

Example

Here is an example of the entryPoint requests_total metric with an additional "useragent" label.

When configuring the label in Static Configuration:

metrics:
  prometheus:
    headerLabels:
      useragent: User-Agent

[metrics]
  [metrics.prometheus]
    [metrics.prometheus.headerLabels]
      useragent = "User-Agent"

--metrics.prometheus.headerlabels.useragent=User-Agent

And performing a request with a custom User-Agent:

curl -H "User-Agent: foobar" http://localhost

The following metric is produced :

traefik_entrypoint_requests_total{code="200",entrypoint="web",method="GET",protocol="http",useragent="foobar"} 1

!!! info "Host header value"

The `Host` header is never present in the Header map of a request, as per go documentation says:
// For incoming requests, the Host header is promoted to the
// Request.Host field and removed from the Header map.

As a workaround, to obtain the Host of a request as a label, one should use instead the `X-Forwarded-For` header.