> ## 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.

# Pairing command

> Connect a server to Techstack by running one personal command in its terminal

The pairing command is the **Give me a 1-liner** path in the Add Node wizard.
You copy one line from Techstack, paste it into the terminal of your server,
and the server connects itself. You do not need to enter SSH details in
Techstack.

## What the command does

The command downloads the Techstack installer from your Techstack and runs it
with a personal, short-lived pairing token. On the server, the installer:

1. detects the platform and installs the Techstack **Guard**, a small agent
   that reports the server's health;
2. installs the pinned StackKits runtime the rollout needs;
3. redeems the pairing token, which links this server to your homelab;
4. installs Docker with `apt-get` when no working container runtime is present;
5. installs and starts the `techstack-agent` system service, so the Guard
   keeps running after a restart.

The Guard talks to Techstack only through an **outbound** HTTPS connection. It
sends a heartbeat and a measured inventory about every 30 seconds. You do not
open an inbound port on the server for it.

The token works once. Techstack stores only a hash of the credential the
server receives, and the command is not kept in job reports.

## Before you run it

* **A Linux server with systemd.** Ubuntu is the standard system; see
  [Add a Node](/techstack/add-node#operating-system).
* **Administrator rights.** Run the command as `root` or as a user that can use
  `sudo`. The installer writes system files and installs a service.
* **`curl` on the server.** The command uses it to download the installer.
* **The server can reach Techstack.** The progress page shows the field
  **Techstack URL reachable from the server**. The address in that field must
  open from the server, not only from your computer. With the
  [Windows Alpha](/techstack/install-windows), the server reaches the Windows
  computer on TCP port `5264` in your local network, so keep the Windows client
  running while you pair.
* **A fresh command.** A pairing token expires 15 minutes after Techstack
  creates it.

## Run the command

1. Finish the Add Node wizard. Techstack opens the progress page for the new
   Node, which shows **Not connected yet**.
2. Check the **Techstack URL reachable from the server** field and correct it
   if the server uses a different address to reach Techstack.
3. Select **Copy pairing command**.
4. Open a terminal on the server, directly or over SSH, paste the command, and
   press Enter. Do not change the command. It contains your personal token.
5. Wait for the installer to finish. It prints each step.

If the page says **This pairing token has expired**, select **Generate new
command** and run the new command instead. The old one no longer works.

<Warning>
  Treat the command like a one-time password. Anyone who runs it before it
  expires can connect a server to your homelab.
</Warning>

## When the Node is connected

When the Guard sends its first heartbeat, Techstack changes the Node from
**Not connected yet** to connected. The progress page then continues with the
StackKit rollout for this Node. You can close the terminal.

To check the Guard on the server later:

* `sudo systemctl status techstack-agent` shows whether the service runs.
* `sudo journalctl -u techstack-agent -f` follows its log.

The Node now appears in your homelab with its health. Where its services are
reachable does not depend on where the server stands: local hardware and
rented servers can both use your own domain or a `*.kombify.me` address. See
[kombify.me](/kombify-me/overview).