Collecting Juju metrics
While it is possible to write charms that collect metrics about charms (see Metric collecting charms), it is also possible to collect metrics about Juju itself. Each controller provides an HTTPS endpoint to expose Prometheus metrics. To feed these metrics into Prometheus, you must add a new scrape target to your already installed and running Prometheus instance. For this use case, the only constraint on where Prometheus is running is that the server must be able to contact the controller’s API address/port.
The Juju controller’s metrics endpoint requires authorisation, so create a user and password for Prometheus to use:
juju add-user prometheus juju change-user-password prometheus
When prompted, enter the password twice:
new password: <password> type new password again: <password>
prometheus user to be able to access the metrics endpoint, grant the user read access to the controller model:
juju grant prometheus read controller
Juju serves the metrics over HTTPS, with no option of degrading to HTTP. You can configure your Prometheus instance to skip validation, or enter this to store the controller’s CA certificate in a file for Prometheus to verify the server’s certificate against:
juju controller-config ca-cert > /path/to/juju-ca.crt
To add a scrape target to Prometheus, add the following to
scrape_configs: job_name: juju metrics_path: /introspection/metrics scheme: https static_configs: targets: ['<controller-address>:17070'] basic_auth: username: user-prometheus password: <password> tls_config: ca_file: /path/to/juju-ca.crt
The username syntax in the scrape_configs is important and should contain the
Last updated a month ago.