5.5. Accessing broker runtime data using Prometheus

Procedure

1. From your Prometheus installation directory, open the prometheus.yml configuration file.
2. In the static_configs section of the configuration file, change the targets element to localhost:8161. This location is where the broker runs its web server. By default, /metrics is appended to this host name, forming the full path to the metrics stored on the broker web server.

3. To view the broker runtime metrics collected by the Prometheus plugin, open localhost:8161/metrics in a web browser.

   On the resulting web page, you see the current values of the metrics collected by the plugin, based on the queues and addresses that you have configured on the broker. If you have more than one running broker instance in your JVM, you see metrics for each broker.

4. From your Prometheus installation directory, run Prometheus.

   $ ./prometheus

   When Prometheus starts, the shell output includes the following line:

   component=web, msg=”Start listening for connections” address=0.0.0.0:9090

   The preceding line indicates that Prometheus is listening for HTTP traffic on port 9090.

5. To access the Prometheus web console, open 127.0.0.1:9090 in a web browser.

6. In the Prometheus web console, you can use the Expression field to create a query on your broker data. The queries you create are based on the Prometheus query language, PromQL. Broker metrics that are available to insert in your query are in the Insert metric drop-down list.

   As a simple example, suppose you want to query the message count on the DLQ queue, over time. In this case, select artemis_message_count from the metrics drop-down list. Complete your query by specifying the DLQ queue name and address. This example query is shown below.

   artemis_message_count{address=“DLQ”, queue=“DLQ”}

   For more advanced visualizations, you can use regular expressions to create complex queries that overlay several metrics, for example. Or, you can perform mathematical operations on a number of metrics, such as aggregating them. For more information about creating Prometheus queries, see Querying Prometheus in the Prometheus documentation.