Connect a server

Every SSH server becomes a tower. GRIDCITY keeps one SSH connection per server and runs one small read-only script on it every two seconds: it reads /proc, df and /etc/os-release. Nothing is installed on the server.

In the app

Press Ctrl+K → Connect a server… (or the button in the empty city).

Where the server is	What you need	User name
AWS (EC2, Lightsail), Oracle Cloud	the key file (.pem/.ppk)	found for you (ubuntu, ec2-user, opc)
Google Cloud	your key, pasted in the console	the one you type
Azure, DigitalOcean, Hetzner, VPS	the key you chose, or the password	azureuser / root by default
Your own server	the password once	yours
Behind a bastion	the key, plus the jump host address	per server

1. Trust. The app reads the server's host key fingerprint. Compare it with the console or dashboard and confirm; it is added to your known_hosts, like answering "yes" in ssh. A key that changed is never trusted automatically: it could be an attack.
2. Key. Pick a key from your ssh-agent or SSH folder, upload a key file (AWS .pem, PuTTY .ppk converted for you, OpenSSH id_*), or create a new one. Copy public key gives you the line for a provider console.
3. Install. If the server does not accept the key yet, type the account password once. The app adds your public key to authorized_keys. The password is never saved or logged.
4. Done. The server is saved to hosts.yaml and its tower lights up.

From ~/.ssh/config

Ctrl+K → Import hosts from ~/.ssh/config, or:

gridcity import-ssh-config

Every concrete Host entry (not wildcards) is added. Safe to run again.

From the command line

gridcity add-host ops@203.0.113.10 --name web-01 --district Hetzner

The connection is tested with the fleet's exact checks first, and saved only if it works.

Editing and removing

Focus a server and press E: rename it, move it to another district, set tags and its own warning thresholds, or remove it. The id never changes, so its place in the city and its history are kept.

By hand

hosts.yaml

hosts:
  - id: web-01
    name: web-01
    address: 203.0.113.10
    user: ops
    district: Hetzner
    tags: [web, prod]
    dependsOn: [orders-db] # drawn as a link in the city

The running app reloads the file when it changes. See Configuration.

If it does not connect

Focus the server and press D. The Doctor checks DNS, the port and the SSH banner, runs the real connection test and tells you exactly what to do. See The Doctor.