# Installation and setup

Constellation runs entirely in your cloud environment and can be controlled via a dedicated command-line interface (CLI).

The following guides you through the steps of installing the CLI on your machine, verifying it, and connecting it to your cloud service provider (CSP).

## Prerequisites

Make sure the following requirements are met:

- Your machine is running Linux or macOS
- You have admin rights on your machine
- [kubectl](https://kubernetes.io/docs/tasks/tools/) is installed
- Your CSP is Microsoft Azure or Google Cloud Platform (GCP)

## Install the Constellation CLI

The CLI executable is available at [GitHub](https://github.com/edgelesssys/constellation/releases).
Install it with the following commands:

<tabs>
<tabItem value="linux-amd64" label="Linux (amd64)">

1. Download the CLI:

```bash
curl -LO https://github.com/edgelesssys/constellation/releases/latest/download/constellation-linux-amd64
```

2. [Verify the signature](../workflows/verify-cli.md) (optional)

3. Install the CLI to your PATH:

```bash
sudo install constellation-linux-amd64 /usr/local/bin/constellation
```

</tabItem>
<tabItem value="linux-arm64" label="Linux (arm64)">

1. Download the CLI:

```bash
curl -LO https://github.com/edgelesssys/constellation/releases/latest/download/constellation-linux-arm64
```

2. [Verify the signature](../workflows/verify-cli.md) (optional)

3. Install the CLI to your PATH:

```bash
sudo install constellation-linux-arm64 /usr/local/bin/constellation
```


</tabItem>

<tabItem value="darwin-arm64" label="macOS (Apple Silicon)">

1. Download the CLI:

```bash
curl -LO https://github.com/edgelesssys/constellation/releases/latest/download/constellation-darwin-arm64
```

2. [Verify the signature](../workflows/verify-cli.md) (optional)

3. Install the CLI to your PATH:

```bash
sudo install constellation-darwin-arm64 /usr/local/bin/constellation
```



</tabItem>

<tabItem value="darwin-amd64" label="macOS (Intel)">

1. Download the CLI:

```bash
curl -LO https://github.com/edgelesssys/constellation/releases/latest/download/constellation-darwin-amd64
```

2. [Verify the signature](../workflows/verify-cli.md) (optional)

3. Install the CLI to your PATH:

```bash
sudo install constellation-darwin-amd64 /usr/local/bin/constellation
```

</tabItem>
</tabs>

:::tip
The CLI supports autocompletion for various shells. To set it up, run `constellation completion` and follow the given steps.
:::

## Set up cloud credentials

The CLI makes authenticated calls to the CSP API. Therefore, you need to set up Constellation with the credentials for your CSP.

### Required permissions

<tabs groupId="csp">
<tabItem value="azure" label="Azure">

You need the following permissions for your user account:

- `Contributor` (to create cloud resources)
- `User Access Administrator` (to create a service account)

If you don't have these permissions with scope *subscription*, ask your administrator to [create the service account and a resource group for your Constellation cluster](first-steps.md).
Your user account needs the `Contributor` permission scoped to this resource group.

</tabItem>
<tabItem value="gcp" label="GCP">

Create a new project for Constellation or use an existing one.
Enable the [Compute Engine API](https://console.cloud.google.com/apis/library/compute.googleapis.com) on it.

You need the following permissions on this project:

- `compute.*` (or the subset defined by `roles/compute.instanceAdmin.v1`)
- `iam.serviceAccountUser`

Follow Google's guide on [understanding](https://cloud.google.com/iam/docs/understanding-roles) and [assigning roles](https://cloud.google.com/iam/docs/granting-changing-revoking-access).

</tabItem>
</tabs>

### Authentication

You need to authenticate with your CSP. The following lists the required steps for *testing* and *production* environments.

:::note
The steps for a *testing* environment are simpler. However, they may expose secrets to the CSP. If in doubt, follow the *production* steps.
:::

<tabs groupId="csp">
<tabItem value="azure" label="Azure">

**Testing**

Simply open the [Azure Cloud Shell](https://docs.microsoft.com/en-us/azure/cloud-shell/overview).

**Production**

Use the latest version of the [Azure CLI](https://docs.microsoft.com/en-us/cli/azure/) on a trusted machine:

```bash
az login
```

Other options are described in Azure's [authentication guide](https://docs.microsoft.com/en-us/cli/azure/authenticate-azure-cli).

</tabItem>
<tabItem value="gcp" label="GCP">

**Testing**

You can use the [Google Cloud Shell](https://cloud.google.com/shell). Make sure your [session is authorized](https://cloud.google.com/shell/docs/auth). For example, execute `gsutil` and accept the authorization prompt.

**Production**

Use one of the following options on a trusted machine:

- Use the [`gcloud` CLI](https://cloud.google.com/sdk/gcloud)

    ```bash
    gcloud auth application-default login
    ```

    This will ask you to log-in to your Google account and create your credentials.
    The Constellation CLI will automatically load these credentials when needed.

- Set up a service account and pass the credentials manually

    Follow [Google's guide](https://cloud.google.com/docs/authentication/production#manually) for setting up your credentials.

</tabItem>
</tabs>

## Next steps

You are now ready to [deploy your first confidential Kubernetes cluster and application](first-steps.md).