> ## Documentation Index
> Fetch the complete documentation index at: https://docs.sreagent.app/llms.txt
> Use this file to discover all available pages before exploring further.

# SLO settings and data sources

> Reference for SLO alert thresholds, tracking failure settings and the data sources an SLI can read.

export const Plan = ({tier}) => <Badge color="blue">{tier} plan</Badge>;

This page lists the settings on an SLO and the data sources an SLI can use. For the task flow, see [Set up SLOs](/guides/prevent/slos).

<Plan tier="Free" />

## Alert settings

Open an SLO and use the pencil icon to edit it. These settings control when it alerts:

| Setting | What it does |
| - | - |
| **Alert on burn rate** | Alerts when the budget is burning faster than the thresholds. |
| **Fast burn threshold** | Compared with the burn rate over the last hour. Default 14.4. |
| **Slow burn threshold** | Compared with the burn rate over the last 6 hours. Default 1.0. |
| **Alert on budget warning** and **Budget warning threshold (%)** | Alerts when the remaining budget falls below the percentage. Default 20%. |
| **Alert on tracking failure**, **Failure threshold (cycles)** and **Failure alert severity** | Alerts when SRE Agent cannot compute the SLO for several cycles in a row. Default 3 cycles, severity warning. |
| **Gate deploys on this SLO** | Default, **Always gate deploys** or **Never gate deploys**. See [Deploy gate](/guides/prevent/deploy-gate). |

A burn rate of 1.0 means you are spending the budget exactly as fast as the window allows. Breach alerts arrive like any other alert, so they can page people and trigger runbooks.

## Data sources an SLO can use

| SLI query type | Query language |
| - | - |
| Prometheus | PromQL |
| CloudWatch Metrics | Metric query (namespace, metric, statistic) |
| Loki | LogQL, wrapped in `count_over_time` or `rate` and summed |
| CloudWatch Logs | Logs Insights, ending in a `stats` aggregation. Set **Default log group** on the data source. |
| Datadog Metrics | Datadog metrics query, with `.as_count()` on counters |
| New Relic Metrics | NRQL, without `SINCE` or `UNTIL`. Set **Account ID** on the data source. |
| Synthetic | A check, not a query |

An SLI is measured either as good events divided by total events, or as a single value compared with a threshold. Only Prometheus, CloudWatch Metrics and Loki sources appear in the wizard. The others you add by hand on **Manage SLIs**.

## Related

* [Connect your data](/guides/get-started/connect-your-data): fields each data source needs.
* [Troubleshooting](/guides/reference/troubleshooting): what to check when an SLO shows degraded.


This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.