Data sources

Loki

Configure

Grafana Cloud Enterprise Open source

Last reviewed: July 29, 2026

Configure the Loki data source

This document explains how to configure the Loki data source and describes the available configuration options. For general information on adding and managing data sources, refer to Data source management.

Grafana includes built-in support for Loki, so you don’t need to install a plugin.

Before you begin

Before you configure the data source, ensure you have:

Grafana permissions: The Organization administrator role to add and configure data sources. Administrators can also configure the data source with YAML provisioning.
Loki server URL: The address of your Loki server, including the port. Loki listens on port 3100 by default.
Authentication details: Any credentials or certificates your Loki server requires, such as a basic auth user and password or TLS certificates.

Note
Use TLS (Transport Layer Security) for an additional layer of security when working with Loki. For information on setting up TLS encryption with Loki, refer to Grafana Loki configuration parameters.

Add the Loki data source

To add the Loki data source:

Click Connections in the left-side menu.
Click Add new connection.
Type Loki in the search bar.
Select the Loki data source.
Click Add new data source in the upper right.

Grafana takes you to the Settings tab, where you set up your Loki configuration.

Configure the data source in the UI

The following sections describe the configuration options available for the Loki data source.

The first options set the name of your connection:

Setting	Description
Name	The data source name. This is how you refer to the data source in panels and queries. Examples: `loki-1`, `loki_logs`.
Default	Toggle to make this the default data source. Grafana selects it by default in new panels and queries.

Connection

Configure how Grafana connects to your Loki server.

Setting	Description
URL	The base URL of your Loki server. If Loki runs locally, use `http://localhost:3100`. If Loki runs on a networked server, use its URL and port, for example `http://loki.example.com:3100`.

Note
Enter only the base URL. Don’t append API paths such as /loki/api/v1/push. That endpoint sends logs to Loki with an agent like Grafana Alloy; it isn’t used to query Loki from the data source.
If your Grafana instance runs on Grafana Cloud, a localhost or private network address refers to Grafana servers rather than your network, so it can’t reach a self-hosted Loki. Use Private data source connect (PDC) to query Loki on a private network.

Authentication

Configure how Grafana authenticates with your Loki server. Select an authentication method and provide any required credentials.

Setting	Description
Basic authentication	The most common authentication method. Enter the user name and password for your Loki server.
Forward OAuth Identity	Toggle on to forward the OAuth access token, and the OIDC ID token if available, of the user querying the data source.
With credentials	Toggle on to send credentials such as cookies or authentication headers with cross-site requests.
TLS Client Auth	Toggle on to authenticate with a client certificate. Provide the Server name, Client cert, and Client key.
With CA cert	Toggle on to verify a self-signed TLS certificate. Follow the instructions from your certificate authority (CA) to obtain the certificate file.
Skip TLS verify	Toggle on to bypass TLS certificate verification. Skipping verification isn’t recommended unless absolutely necessary or for testing.

Note
For Grafana Cloud-hosted Loki, use Basic authentication with your Grafana Cloud user ID as the user name and a Cloud Access Policy token as the password. The token’s access policy must include the logs:read scope. Create tokens in the Grafana Cloud Portal. A token’s value is shown only once, so copy it when you create it.

Custom HTTP headers

Add custom HTTP headers to pass values that your Loki instance requires.

Setting	Description
Header	The name of the custom header.
Value	The value of the header.

For a multi-tenant Loki, one configured with auth_enabled: true, add the X-Scope-OrgID header with your tenant ID so Loki knows which tenant to query. Without it, queries against a multi-tenant Loki fail with an authentication error or return no data.

Additional settings

The Additional settings section is collapsible and contains optional settings that give you more control over the data source. It’s open by default and includes advanced HTTP settings, alerting, query, and derived field options.

Advanced HTTP settings

Configure additional HTTP behavior for requests to Loki.

Setting	Description
Allowed cookies	Specify cookies by name that should be forwarded to the data source. By default, the Grafana proxy deletes forwarded cookies.
Timeout	The HTTP request timeout, in seconds. There’s no default, so set a value that suits your queries.

Secure Socks Proxy

The Secure Socks Proxy settings appear only when the secure SOCKS data source proxy is enabled in the Grafana configuration file. When enabled, you can route data source requests through a secure SOCKS proxy. For more information, refer to Configure a data source connection proxy.

Alerting

Configure how the data source works with Grafana Alerting.

Setting	Description
Manage alert rules in Alerting UI	Toggle on to manage data source-managed alert rules for the Loki data source in the Grafana Alerting UI. These rules are stored and evaluated by the Loki ruler. The default follows your Grafana configuration.

To manage other alerting resources, such as the alerts these rules generate, add an Alertmanager data source. For more information on alerting with Loki, refer to Loki alerting.

Queries

Configure query behavior for the data source.

Setting	Description
Maximum lines	Sets the maximum number of log lines Loki returns. Increase the limit for a larger result set for ad hoc analysis. Decrease the limit if your browser is slow when displaying log results. The default is `1000`.

Derived fields

Use derived fields to extract new fields from your logs and create a link from the value of the field.

For example, you can link to your tracing backend directly from your logs, or link to a user profile page when a log line contains a corresponding userId. These links appear in the log details.

You can add multiple derived fields.

Note
If you use Grafana Cloud, you can request modifications to this feature by opening a support ticket from the Grafana Cloud Portal.

Each derived field has the following options:

Setting	Description
Name	The field name. Displayed as a label in the log details.
Type	The type of the derived field. Choose Regex in log line to parse a value from the log content, or Label to match a label key.
Regex	When the type is Regex in log line, a regular expression that parses part of the log message. Include a capture group; Grafana uses the first captured group as the field value.
Label	When the type is Label, the input matches as a regular expression against label keys, so a pattern like `trace[_]?id` matches variations such as `traceid` and `trace_id`. Matches any label: indexed, parsed, or structured metadata.
URL/query	The full link URL for external links, or a query for the target data source for internal links. Interpolate the field value with the `${__value.raw}` macro.
URL Label