In order to fetch data from Jaeger, Kiali needs to get an URL that can be resolved from inside the cluster, typically using Kubernetes DNS. This is the
in_cluster_url configuration. For instance, for a Jaeger service named
istio-system namespace, Kiali config would be:
external_services: tracing: in_cluster_url: 'http://tracing.istio-system/jaeger'
If you use the Kiali operator (recommended), this config can be set in the Kiali CR. But in most cases, the Kiali operator will set a valid default
in_cluster_url so you wouldn’t have to change anything. If you don’t use the Kiali operator, this config can be set in Kiali config map.
Configuring an external URL for Jaeger will enable links from Kiali to Jaeger UI. This URL needs to be accessible from the browser (it’s used for links generation). Example:
external_services: tracing: in_cluster_url: 'http://tracing.istio-system/jaeger' url: 'http://my-jaeger-host/jaeger'
Once this URL is set, Kiali will show an additional item to the main menu:
You may have
url configured and not
in_cluster_url, for instance, if Jaeger is not accessible from Kiali pod. In this situation, Kiali will not show its own traces chart but will display external links to the Jaeger UI instead.
The tracing view is accessible if the in-cluster URL is correctly configured. Each service page will show the Traces tab where a scatter plot is displayed with its related traces.
Kiali allows interactions with Jaeger UI via external links: For example, "View Trace in Tracing" goes to the Jaeger UI trace view.
The tracing toolbar offers some control over the data to fetch, to facilitate the user experience. In the tracing view, as shown in the image below, it’s possible to select the traces interval, results limit, status code, errors, adjust time (expand results on time), last Xm traffic (Traces from last minutes) and refresh interval.
After selecting a trace, Kiali shows the information related to that trace like number of spans, spans grouped by operation name, duration, date…
In each span, tags and processes are displayed.