Grafana includes built-in support for Prometheus. This topic explains options, variables, querying, and other options specific to the Prometheus data source. Refer to [Add a data source]({{< relref "add-a-data-source.md" >}}) for instructions on how to add a data source to Grafana. Only users with the organization admin role can add data sources.
To access Prometheus settings, hover your mouse over the **Configuration** (gear) icon, then click **Data Sources**, and then click the Prometheus data source.
| _Custom Query Parameters_ | Add custom parameters to the Prometheus query URL. For example `timeout`, `partial_response`, `dedup`, or `max_source_resolution`. Multiple parameters should be concatenated together with an '&'. |
| _Legend format_ | Controls the name of the time series, using name or pattern. For example `{{hostname}}` is replaced with the label value for the label `hostname`. |
| _Min step_ | An additional lower limit for the [`step` parameter of Prometheus range queries](https://prometheus.io/docs/prometheus/latest/querying/api/#range-queries) and for the `$__interval` variable. The limit is absolute and not modified by the _Resolution_ setting. |
| _Resolution_ | `1/1` sets both the `$__interval` variable and the [`step` parameter of Prometheus range queries](https://prometheus.io/docs/prometheus/latest/querying/api/#range-queries) such that each pixel corresponds to one data point. For better performance, lower resolutions can be picked. `1/2` only retrieves a data point for every other pixel, and `1/10` retrieves one data point per 10 pixels. Note that both _Min time interval_ and _Min step_ limit the final value of `$__interval` and `step`. |
| _Format as_ | Switch between `Table`, `Time series` or `Heatmap`. `Table` will only work in the Table panel. `Heatmap` is suitable for displaying metrics of the Histogram type on a Heatmap panel. Under the hood, it converts cumulative histograms to regular ones and sorts series by the bucket bound. |
| _Instant_ | Perform an "instant" query, to return only the latest value that Prometheus has scraped for the requested time series. Instant queries return results much faster than normal range queries. Use them to look up label sets. |
| _Min time interval_| This value multiplied by the denominator from the _Resolution_ setting sets a lower limit to both the `$__interval` variable and the [`step` parameter of Prometheus range queries](https://prometheus.io/docs/prometheus/latest/querying/api/#range-queries). Defaults to _Scrape interval_ as set in the data source options. |
> **Note:** Grafana modifies the request dates for queries to align them with the dynamically calculated step. This ensures consistent display of metrics data, but it can result in a small gap of data at the right edge of a graph.
Instant query results are made up only of one data point per series but can be shown in the graph panel with the help of [series overrides]({{< relref "../../panels/visualizations/graph-panel.md#series-overrides" >}}).
Check out the [Templating]({{< relref "../../variables/templates-and-variables.md" >}}) documentation for an introduction to the templating feature and the different
For details of what _metric names_, _label names_ and _label values_ are please refer to the [Prometheus documentation](http://prometheus.io/docs/concepts/data_model/#metric-names-and-labels).
You can use some global built-in variables in query variables; `$__interval`, `$__interval_ms`, `$__range`, `$__range_s` and `$__range_ms`, see [Global built-in variables]({{< relref "../../variables/variable-types/global-variables.md" >}}) for more information. These can be convenient to use in conjunction with the `query_result` function when you need to filter variable queries since
Make sure to set the variable's `refresh` trigger to be `On Time Range Change` to get the correct instances when changing the time range on the dashboard.
The `$__rate_interval` variable is meant to be used in the rate function. It is defined as max( `$__interval` + _Scrape interval_, 4 * _Scrape interval_), where _Scrape interval_ is the Min step setting (AKA query_interval, a setting per PromQL query), if any is set, and otherwise the _Scrape interval_ as set in the Prometheus data source (but ignoring any Min interval setting in the panel, because the latter is modified by the resolution setting).
Why two ways? The first syntax is easier to read and write but does not allow you to use a variable in the middle of a word. When the _Multi-value_ or _Include all value_
- A Prometheus query for pending and firing alerts (for details see [Inspecting alerts during runtime](https://prometheus.io/docs/prometheus/latest/configuration/alerting_rules/#inspecting-alerts-during-runtime))
Grafana exposes metrics for Prometheus on the `/metrics` endpoint. We also bundle a dashboard within Grafana so you can get started viewing your metrics faster. You can import the bundled dashboard by going to the data source edit page and click the dashboard tab. There you can find a dashboard for Grafana and one for Prometheus. Import and start viewing all the metrics!
For detailed instructions, refer to [Internal Grafana metrics]({{< relref "../../administration/metrics.md">}}).
You can configure data sources using config files with Grafana's provisioning system. Read more about how it works and all the settings you can set for data sources on the [provisioning docs page]({{< relref "../../administration/provisioning/#datasources" >}})
