Prometheus, Jaeger and Grafana

Prometheus configuration

Kiali requires Prometheus to generate the topology graph, show metrics, calculate health and for several other features. If Prometheus is missing or Kiali can’t reach it, Kiali won’t work properly.

By default, Kiali assumes that Prometheus is available at the URL of the form http://prometheus.<istio_namespace_name>:9090, which is the usual case if you are using the Prometheus Istio add-on. If your Prometheus instance has a different service name or is installed to a different namespace, you must manually provide the endpoint where it is available, like in the following example:

spec:
  external_services:
    prometheus:
      # Prometheus service name is "metrics" and is in the "telemetry" namespace
      url: "http://metrics.telemetry:9090/"

Kiali maintains an internal cache of some Prometheus queries to improve performance (mainly, the queries to calculate Health indicators). It would be very rare to see data delays, but should you notice any delays you may tune caching parameters to values that work better for your environment. These are the default values:

spec:
  external_services:
    prometheus:
      cache_enabled: true
      # Per-query expiration in seconds
      cache_duration: 10
      # Global cache expiration in seconds. Think of it as
      # the "reset" or "garbage collection" interval.
      cache_expiration: 300

Compatibility with Prometheus-like servers

Although Kiali assumes a Prometheus server and is tested against it, there are TSDBs that can be used as Prometheus replacement despite not implementing the full Prometheus API.

Community users have faced two issues when using Prometheus-like TSDBs:

• Kiali may report that the TSDB is unreachable, and/or
• Kiali may show empty metrics if the TSBD does not implement the /api/v1/status/config.

To fix these issues, you may need to provide a custom health check endpoint for the TSDB and/or manually provide the configurations that Kiali reads from the /api/v1/status/config API endpoint:

spec:
  external_services:
    prometheus:
      # Fix the "Unreachable" metrics server warning.
      health_check_url: "http://custom-tsdb-health-check-url"
      # Fix for the empty metrics dashboards
      thanos_proxy:
        enabled: true
        retention_period: "7d"
        scrape_interval: "30s"

Jaeger configuration

Jaeger is a highly recommended service because Kiali uses distributed tracing data for several features, providing an enhanced experience.

By default, Kiali will try to reach Jaeger at the GRPC-enabled URL of the form http://tracing.<istio_namespace_name>:16685/jaeger, which is the usual case if you are using the Jaeger Istio add-on. If this endpoint is unreachable, Kiali will disable features that use distributed tracing data.

If your Jaeger instance has a different service name or is installed to a different namespace, you must manually provide the endpoint where it is available, like in the following example:

spec:
  external_services:
    tracing:
      # Enabled by default. Kiali will anyway fallback to disabled if
      # Jaeger is unreachable.
      enabled: true
      # Jaeger service name is "tracing" and is in the "telemetry" namespace.
      # Make sure the URL you provide corresponds to the non-GRPC enabled endpoint
      # if you set "use_grpc" to false.
      in_cluster_url: 'http://tracing.telemetry:16685/jaeger'
      use_grpc: true
      # Public facing URL of Jaeger
      url: 'http://my-jaeger-host/jaeger'

Minimally, you must provide spec.external_services.tracing.in_cluster_url to enable Kiali features that use distributed tracing data. However, Kiali can provide contextual links that users can use to jump to the Jaeger console to inspect tracing data more in depth. For these links to be available you need to set the spec.external_services.tracing.url which may mean that you should expose Jaeger outside the cluster.

Grafana configuration

Istio provides preconfigured Grafana dashboards for the most relevant metrics of the mesh. Although Kiali offers similar views in its metrics dashboards, it is not in Kiali’s goals to provide the advanced querying options, nor the highly customizable settings, that are available in Grafana. Thus, it is recommended that you use Grafana if you need those advanced options.

Kiali can provide a direct link from its metric dashboards to the equivalent or most similar Grafana dashboard, which is convenient if you need the powerful Grafana options. For these links to appear in Kiali you need to manually configure what is the Grafana URL, like in the following example:

spec:
  external_services:
    grafana:
      enabled: true
      # Grafana service name is "grafana" and is in the "telemetry" namespace.
      in_cluster_url: 'http://grafana.telemetry:3000/'
      # Public facing URL of Grafana
      url: 'http://my-ingress-host/grafana'