Prometheus

Grafana includes support for Prometheus Datasources. While the process of adding the datasource is similar to adding a Graphite or OpenTSDB datasource type, Prometheus does have a few different options for building queries.

Adding the data source to Grafana

1. Open the side menu by clicking the the Grafana icon in the top header.

2. In the side menu under the Dashboards link you should find a link named Data Sources.

   NOTE: If this link is missing in the side menu it means that your current user does not have the Admin role for the current organization.

3. Click the Add new link in the top header.

4. Select Prometheus from the dropdown.

Name	Description
Name	The data source name, important that this is the same as in Grafana v1.x if you plan to import old dashboards.
Default	Default data source means that it will be pre-selected for new panels.
Url	The http protocol, ip and port of you Prometheus server (default port is usually 9090)
Access	Proxy = access via Grafana backend, Direct = access directory from browser.
Basic Auth	Enable basic authentication to the Prometheus datasource.
User	Name of your Prometheus user
Password	Database user's password

Proxy access means that the Grafana backend will proxy all requests from the browser, and send them on to the Data Source. This is useful because it can eliminate CORS (Cross Origin Site Resource) issues, as well as eliminate the need to disseminate authentication details to the Data Source to the browser.

Direct access is still supported because in some cases it may be useful to access a Data Source directly depending on the use case and topology of Grafana, the user, and the Data Source.

Query editor

Open a graph in edit mode by click the title.

For details on Prometheus metric queries check out the Prometheus documentation - Query Metrics - Prometheus documentation.

Templated queries

Prometheus Datasource Plugin provides the following functions in Variables values query field in Templating Editor to query metric names and labels names on the Prometheus server.

Name	Description
label_values(label)	Returns a list of label values for the label in every metric.
label_values(metric, label)	Returns a list of label values for the label in the specified metric.
metrics(metric)	Returns a list of metrics matching the specified metric regex.

For details of metric names & label names, and label values, please refer to the Prometheus documentation.

You can create a template variable in Grafana and have that variable filled with values from any Prometheus metric exploration query. You can then use this variable in your Prometheus metric queries.

For example you can have a variable that contains all values for label hostname if you specify a query like this in the templating edit view.

label_values(hostname)

You can also use raw queries & regular expressions to extract anything you might need.