# Getting started

Use Porsche to manage machines over SSH, with the same account and permissions
as Marshall’s web interface.

## Register your key

Sign in to Marshall using your email login and open
[SSH keys](/settings/ssh-keys). Paste one OpenSSH public key and optionally give it
a label. Paste the `.pub` file, never the private key. Supported public keys are
Ed25519, ECDSA and RSA (at least 2048 bits). Certificates and `authorized_keys`
options are not accepted.

The page shows each key's label, type, fingerprint and creation time. Remove a key
to revoke its access. You may remove your last SSH key and continue using email
login. Adding the same public key again creates a new registration; previous
sessions remain revoked.

## Connect

Use the Porsche hostname supplied by your operator. In a local terminal, run
`ssh YOUR_PORSCHE_HOST help` for one command, or `ssh YOUR_PORSCHE_HOST` for an
interactive prompt. Verify the server host-key fingerprint using your operator's
trusted instructions. Management uses port 22.

For browser approval of an unknown key, start an interactive connection with
`ssh YOUR_PORSCHE_HOST` and keep it open. Porsche gives you a short-lived approval
link after proving possession of the private key. Open it in your browser, sign
in, compare the fingerprint and explicitly approve. Opening the link alone does
not register a key. Links expire after ten minutes and stop working when their
SSH connection closes. The interactive prompt can continue after approval.

For one-shot exec commands, register the key on Marshall's SSH keys page first,
or complete approval in an interactive connection before retrying the command.

## First commands

At the Porsche prompt, enter:

```porsche
whoami
images
ls
new --name example-machine
show example-machine
stop example-machine
start example-machine
```

With exec, place the same command after `ssh YOUR_PORSCHE_HOST` and quote it for
your local shell when needed. Porsche does not evaluate shell expressions,
pipelines or substitutions. Single and double quotes group command arguments.

Machine references accept names or UUIDs. Names are lowercase, begin with a letter,
and contain letters, digits and single separating hyphens, up to 63 characters.
UUID-shaped names are reserved for machine identifiers.
Creation without a name generates one. Creation without an image selects the
operator's default image. Omitted CPU, memory and disk requests use defaults raised
to the image minimum; explicitly undersized requests fail.

Stop retains the disk. `rm MACHINE` deletes the machine and its disk. A name is
available for reuse only after cleanup is confirmed. Use `exit` to leave the prompt.

VM disks have a maximum capacity of **500 GiB** (536,870,912,000 bytes).
Creation and resize requests above this limit are rejected, including Porsche
`new --disk` requests.