Monitoring with Istio

Monitoring is crucial to support transitioning to the microservices architecture style. Other requirements include rapid provisioning and rapid deployment, according to this article.

With Istio, you gain monitoring of the traffic between microservices by default. You can use the Istio Dashboard for monitoring your microservices in real time.

Istio is integrated out-of-the-box with Prometheus time series database and monitoring system. Prometheus collects various traffic-related metrics and provides a rich query language for them.

See below several examples of Prometheus Istio-related queries.

1. Access the Prometheus UI at http://my-istio-logs-database.io. (The my-istio-logs-database.io URL should be in your /etc/hosts file, you set it previously).

   

2. Run the following example queries in the Expression input box. Push the Execute button to see query results in the Console tab. The queries use tutorial as the name of the application’s namespace, substitute it with the name of your namespace. For best results, run the real-time traffic simulator described in the previous steps when querying data.

   1. Get all the requests in your namespace:

      istio_requests_total{destination_service_namespace="tutorial", reporter="destination"}
      

   2. Get the sum of all the requests in your namespace:

      sum(istio_requests_total{destination_service_namespace="tutorial", reporter="destination"})
      

   3. Get the requests to reviews microservice:

      istio_requests_total{destination_service_namespace="tutorial", reporter="destination",destination_service_name="reviews"}
      

   4. Rate of requests over the past 5 minutes to all instances of the reviews microservice:

      rate(istio_requests_total{destination_service_namespace="tutorial", reporter="destination",destination_service_name="reviews"}[5m])
      

The queries above use the istio_requests_total metric, which is a standard Istio metric. You can observe other metrics, in particular, the ones of Envoy (Envoy is the sidecar proxy of Istio). You can see the collected metrics in the insert metric at cursor drop-down menu.

You are ready to enable mutual TLS authentication with Istio.