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

# Register a server

> Add an Ubuntu host, connect an SSH key, and verify its host identity.

A server is a workspace-owned Ubuntu 22.04 or 24.04 LTS host that Towbar reaches over SSH. Multiple repositories can use the same registered host. Registration establishes connection and trust; [setup](/docs/servers/setup) prepares the runtime afterward.

## Add the connection

1. Open **Servers → Add server** and enter the canonical IP, SSH username and port, and build-concurrency limits.
2. Under **Settings → Configuration**, select a stored [SSH key](/docs/ssh-keys). Install its public key in the SSH user's `~/.ssh/authorized_keys`.
3. Save the connection. Towbar authenticates, reads the host key, and shows its fingerprint.
4. Compare that fingerprint against the server console or another independent channel before accepting it.

The SSH user needs passwordless `sudo` for preparation and workload operations. Keep SSH restricted at the network layer. Docker access is root-equivalent, so use a dedicated deployment account.

The **Host verified** badge records successful trust. If the host key changes later, Towbar stops connecting until you verify the new fingerprint. A rebuild can change the key, but never approve a change solely because the IP is familiar.

## Give the host a name

In **Settings → Configuration → Server info**, save an optional name such as `Build server Mumbai`. Towbar uses it in navigation and the server table, while the IP remains visible in its own column. Renaming does not alter SSH connectivity or require setup again.