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

# Connect a server over SSH

> Let Techstack sign in to your server over SSH and connect it for you

Choose **Connect my device** in the Add Node wizard when your server already
accepts SSH logins and you prefer not to paste a command yourself. Techstack
signs in with the details below, runs the same setup as the
[pairing command](/techstack/pairing-command), and waits for the server's
Guard to register.

## Host or IP address

Enter the address Techstack uses to reach the server in **Node host or IP**,
for example `192.168.1.20` or `server.example.com`.

The address must be reachable from where Techstack runs. A home address like
`192.168.1.20` works when Techstack runs in the same network, for example the
[Windows Alpha](/techstack/install-windows) on a computer at home. If Techstack
cannot reach the server this way, use the
[pairing command](/techstack/pairing-command) instead: the server then
connects outward on its own.

## SSH key or password

Under **Authentication**, choose how Techstack signs in:

* **SSH key.** Techstack uses a private key you saved in your Wallet.
* **Password.** Techstack uses the SSH password of the user you enter.

When you choose a password, the wizard keeps it only in the browser's memory
while you move to the next page. It is not written to the browser's session
storage, so if you reload the page before setup starts, enter the password
again. Techstack then saves the password encrypted in your Wallet for this
StackKit, so it can retry the setup. It is not stored as plain text in the
StackKit configuration or in job reports.

## SSH key label

With **SSH key**, enter the **SSH key label**: the name of an SSH key saved in
your Wallet. Techstack looks up the Wallet item with that name (upper and lower
case do not matter) and uses its private key. You never paste the private key
into the wizard.

If no SSH key in your Wallet has that name, the connection test and the setup
stop with an error. Save the key in your Wallet first, then enter its name
here. The public half of the key must be in the server user's
`~/.ssh/authorized_keys` file, as for any SSH login.

## SSH user, port and sudo

Open **SSH details** to change the defaults:

* **SSH user.** The account Techstack signs in as. The default is `root`.
* **SSH port.** The default is `22`. Change it only if your server's SSH
  service listens on another port.
* **Use sudo for setup commands.** Turn this on when the SSH user is not
  `root`. Techstack then runs the setup with `sudo`. It first tries `sudo`
  without a password prompt, so the setup is most reliable when that user may
  run `sudo` without typing a password. The setup stops if the user has no
  `sudo` at all.

## Test connection

Select **Test connection** before you continue. Techstack tries to sign in
with the address, user, port, and key or password you entered, and shows
**SSH connection successful** or the error it received. The test only signs
in. It does not change anything on the server.

If you change any field after a test, the result is cleared. Test again before
you continue.

Common reasons a test fails:

* the host or IP is wrong, or not reachable from where Techstack runs;
* the SSH port is different from `22`;
* the key label does not match an SSH key in your Wallet;
* the server does not accept that key or password for that user.