--- title: Collecting Logs with Mixer description: This task shows you how to configure Istio's Mixer to collect and customize logs. weight: 10 keywords: [telemetry,logs] aliases: - /docs/tasks/observability/logs/collecting-logs/ - /docs/tasks/telemetry/logs/collecting-logs/ test: n/a --- {{< warning >}} Mixer is deprecated. The functionality provided by Mixer is being moved into the Envoy proxies. Use of Mixer with Istio will only be supported through the 1.7 release of Istio. {{}} This task shows how to configure Istio to automatically gather telemetry for services in a mesh. At the end of this task, a new log stream will be enabled for calls to services within your mesh. The [Bookinfo](/docs/examples/bookinfo/) sample application is used as the example application throughout this task. ## Before you begin * [Install Istio](/docs/setup) in your cluster and deploy an application. This task assumes that Mixer is setup in a default configuration (`--configDefaultNamespace=istio-system`). If you use a different value, update the configuration and commands in this task to match the value. ## Collecting new logs data 1. Apply a YAML file with configuration for the new log stream that Istio will generate and collect automatically. {{< text bash >}} $ kubectl apply -f @samples/bookinfo/telemetry/log-entry.yaml@ {{< /text >}} {{< warning >}} If you use Istio 1.1.2 or prior, please use the following configuration instead: {{< text bash >}} $ kubectl apply -f @samples/bookinfo/telemetry/log-entry-crd.yaml@ {{< /text >}} {{< /warning >}} 1. Send traffic to the sample application. For the Bookinfo sample, visit `http://$GATEWAY_URL/productpage` in your web browser or issue the following command: {{< text bash >}} $ curl http://$GATEWAY_URL/productpage {{< /text >}} 1. Verify that the log stream has been created and is being populated for requests. In a Kubernetes environment, search through the logs for the `istio-telemetry` pods as follows: {{< text bash json >}} $ kubectl logs -n istio-system -l istio-mixer-type=telemetry -c mixer | grep "newlog" | grep -v '"destination":"telemetry"' | grep -v '"destination":"pilot"' | grep -v '"destination":"policy"' | grep -v '"destination":"unknown"' {"level":"warn","time":"2018-09-15T20:46:36.009801Z","instance":"newlog.xxxxx.istio-system","destination":"details","latency":"13.601485ms","responseCode":200,"responseSize":178,"source":"productpage","user":"unknown"} {"level":"warn","time":"2018-09-15T20:46:36.026993Z","instance":"newlog.xxxxx.istio-system","destination":"reviews","latency":"919.482857ms","responseCode":200,"responseSize":295,"source":"productpage","user":"unknown"} {"level":"warn","time":"2018-09-15T20:46:35.982761Z","instance":"newlog.xxxxx.istio-system","destination":"productpage","latency":"968.030256ms","responseCode":200,"responseSize":4415,"source":"istio-ingressgateway","user":"unknown"} {{< /text >}} ## Understanding the logs configuration In this task, you added Istio configuration that instructed Mixer to automatically generate and report a new log stream for all traffic within the mesh. The added configuration controlled three pieces of Mixer functionality: 1. Generation of *instances* (in this example, log entries) from Istio attributes 1. Creation of *handlers* (configured Mixer adapters) capable of processing generated *instances* 1. Dispatch of *instances* to *handlers* according to a set of *rules* The logs configuration directs Mixer to send log entries to stdout. It uses three stanzas (or blocks) of configuration: *instance* configuration, *handler* configuration, and *rule* configuration. The `kind: instance` stanza of configuration defines a schema for generated log entries (or *instances*) named `newlog`. This instance configuration tells Mixer _how_ to generate log entries for requests based on the attributes reported by Envoy. The `severity` parameter is used to indicate the log level for any generated `logentry`. In this example, a literal value of `"warning"` is used. This value will be mapped to supported logging levels by a `logentry` *handler*. The `timestamp` parameter provides time information for all log entries. In this example, the time is provided by the attribute value of `request.time`, as provided by Envoy. The `variables` parameter allows operators to configure what values should be included in each `logentry`. A set of expressions controls the mapping from Istio attributes and literal values into the values that constitute a `logentry`. In this example, each `logentry` instance has a field named `latency` populated with the value from the attribute `response.duration`. If there is no known value for `response.duration`, the `latency` field will be set to a duration of `0ms`. The `kind: handler` stanza of configuration defines a *handler* named `newloghandler`. The handler `spec` configures how the `stdio` compiled adapter code processes received `logentry` instances. The `severity_levels` parameter controls how `logentry` values for the `severity` field are mapped to supported logging levels. Here, the value of `"warning"` is mapped to the `WARNING` log level. The `outputAsJson` parameter directs the adapter to generate JSON-formatted log lines. The `kind: rule` stanza of configuration defines a new *rule* named `newlogstdio`. The rule directs Mixer to send all `newlog` instances to the `newloghandler` handler. Because the `match` parameter is set to `true`, the rule is executed for all requests in the mesh. A `match: true` expression in the rule specification is not required to configure a rule to be executed for all requests. Omitting the entire `match` parameter from the `spec` is equivalent to setting `match: true`. It is included here to illustrate how to use `match` expressions to control rule execution. ## Cleanup * Remove the new logs configuration: {{< text bash >}} $ kubectl delete -f @samples/bookinfo/telemetry/log-entry.yaml@ {{< /text >}} If you are using Istio 1.1.2 or prior: {{< text bash >}} $ kubectl delete -f @samples/bookinfo/telemetry/log-entry-crd.yaml@ {{< /text >}} * If you are not planning to explore any follow-on tasks, refer to the [Bookinfo cleanup](/docs/examples/bookinfo/#cleanup) instructions to shutdown the application.