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

# Running RDT in a Container

> Run RDT from a pre-built container image instead of installing it directly.

If you've been given a pre-built RDT container image (or an image tar), you can run
`rdt` through it without installing anything on your control node besides Docker.

## Prerequisites

* Docker, or a compatible CLI such as Podman (set `DOCKER=podman` if so).
* The `rdt.sh` wrapper script (shipped alongside the image).

## Running commands

Use the wrapper script exactly as you would the `rdt` binary: it forwards all
arguments:

```bash theme={null}
./rdt.sh --help
./rdt.sh config create --name my-regattadb --from xsmall --ip-list 10.0.0.1
./rdt.sh config list
./rdt.sh create-cluster --name my-regattadb --src /path/to/regatta-rpms
```

It automatically mounts your `~/.rdt` config directory and `~/.ssh` keys into the
container and runs with host networking, so configs and SSH access work the same as a
native install.

## Providing the image

If you weren't given an already-loaded Docker image, load one from a tar file
explicitly:

```bash theme={null}
./rdt.sh --src rdt_image.tar config list
```

Otherwise, the wrapper looks for an image automatically, in this order:

1. An existing Docker image tagged `rdt:<version>` or `rdt:latest`.
2. A tar at `$RDT_DOCKER_IMAGE_PATH` (default: `/opt/regatta/current/tools/rdt/rdt_image.tar`).
3. `rdt_image.tar` in the current working directory.

If none of these are found, the wrapper reports an error. See
`./rdt.sh --help` for the full set of flags and environment variables.

## Environment variables

| Variable                | Default                                        | Description                           |
| ----------------------- | ---------------------------------------------- | ------------------------------------- |
| `DOCKER`                | `docker`                                       | Docker CLI binary to use              |
| `RDT_DOCKER_IMAGE_FILE` | `rdt_image.tar`                                | Tar filename used for auto-discovery  |
| `RDT_DOCKER_IMAGE_PATH` | `/opt/regatta/current/tools/rdt/rdt_image.tar` | Full tar path used for auto-discovery |