---
title: "Command line flags | Grafana Tempo documentation"
description: "Reference for Tempo command line flags"
---

# Command line flags

Tempo provides various command-line flags to configure its behavior when starting the binary. This document serves as a reference for these flags.

## Global flags

Expand table

| Flag                        | Description                                            | Default |
|-----------------------------|--------------------------------------------------------|---------|
| `--version`                 | Print this build’s version information and exit        | `false` |
| `--mem-ballast-size-mbs`    | Size of memory ballast to allocate in MBs              | `0`     |
| `--mutex-profile-fraction`  | Override default mutex profiling fraction              | `0`     |
| `--block-profile-threshold` | Override default block profiling threshold             | `0`     |
| `--config.file`             | Configuration file to load                             |         |
| `--config.expand-env`       | Whether to expand environment variables in config file | `false` |
| `--config.verify`           | Verify configuration and exit                          | `false` |

## Target flag

The deployment mode is determined by the runtime configuration `target`, or by using the `-target` flag on the command line. The default target is `all`, which is the monolithic deployment mode.

Expand table

| Flag       | Description          | Default |
|------------|----------------------|---------|
| `--target` | Target module to run | `all`   |

Refer to the [Plan your Tempo deployment](../plan/) documentation for information on deployment modes.

## Authentication and multitenancy

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| Flag                     | Description                                                       | Default |
|--------------------------|-------------------------------------------------------------------|---------|
| `--auth.enabled`         | Set to true to enable auth (deprecated: use multitenancy.enabled) | `false` |
| `--multitenancy.enabled` | Set to true to enable multitenancy                                | `false` |

## HTTP and API settings

Expand table

| Flag                          | Description                                   | Default |
|-------------------------------|-----------------------------------------------|---------|
| `--http-api-prefix`           | String prefix for all HTTP API endpoints      | `""`    |
| `--enable-go-runtime-metrics` | Set to true to enable all Go runtime metrics  | `false` |
| `--shutdown-delay`            | How long to wait between SIGTERM and shutdown | `0`     |

## Server settings

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| Flag                        | Description             | Default |
|-----------------------------|-------------------------|---------|
| `--server.http-listen-port` | HTTP server listen port | `80`    |
| `--server.grpc-listen-port` | gRPC server listen port | `9095`  |

## Memberlist settings

Expand table

| Flag                                        | Description                                  | Default |
|---------------------------------------------|----------------------------------------------|---------|
| `--memberlist.host-port`                    | Host port to connect to memberlist cluster   |         |
| `--memberlist.bind-port`                    | Port for memberlist to communicate on        | `7946`  |
| `--memberlist.message-history-buffer-bytes` | Size in bytes for the message history buffer | `0`     |

## MCP server

Expand table

| Flag                                  | Description                          | Default |
|---------------------------------------|--------------------------------------|---------|
| `--query-frontend.mcp-server.enabled` | Set to true to enable the MCP server | `false` |

Tempo includes an [MCP (Model Context Protocol)](https://modelcontextprotocol.io/docs/getting-started/intro) server that provides AI assistants and Large Language Models (LLMs) with direct access to distributed tracing data through TraceQL queries and other endpoints.

Refer to the [Model Context Protocol (MCP) Server documentation](/docs/tempo/latest/api_docs/mcp-server/) for more information.

## Module configuration

You can use additional flags to configuring individual Tempo modules, such as the distributor, ingester, querier, and their components. These flags follow a pattern like `--<module>.<setting>` and are extensively documented in the configuration file format.

Use the configuration file approach described in the [Configuration documentation](/docs/tempo/latest/configuration/). The documentation has a comprehensive list of all configuration options.

## Usage examples

Start Tempo with a configuration file:

Bash ![Copy code to clipboard](/media/images/icons/icon-copy-small-2.svg) Copy

```bash
tempo --config.file=/etc/tempo/config.yaml
```

Start Tempo with a specific target:

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```bash
tempo --target=distributor --config.file=/etc/tempo/config.yaml
```

Verify configuration without starting Tempo:

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```bash
tempo --config.file=/etc/tempo/config.yaml --config.verify
```

Print version information:

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```bash
tempo --version
```