Generate and Upload SSH Keys

SSH key authentication is more secure than password-based login and is the recommended way to access your servers. This guide explains how to generate a key pair and upload the public key to LightYear.

Generate an SSH Key Pair

macOS and Linux

Open a terminal and run:

$ssh-keygen -t ed25519 -C "[email protected]"

You will be prompted to choose a file location (press Enter to accept the default ~/.ssh/id_ed25519) and an optional passphrase.

Generating public/private ed25519 key pair.
Enter file in which to save the key (/home/user/.ssh/id_ed25519):
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /home/user/.ssh/id_ed25519
Your public key has been saved in /home/user/.ssh/id_ed25519.pub
The key fingerprint is:
SHA256:abc123xyz... [email protected]

[!TIP] Use a passphrase for additional security. You can use ssh-agent to avoid re-entering it on every connection.

Windows (PowerShell)

$ssh-keygen -t ed25519 -C "[email protected]"

The key pair is saved to C:\Users\YourName\.ssh\id_ed25519 and id_ed25519.pub.

View Your Public Key

$cat ~/.ssh/id_ed25519.pub

ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAI... [email protected]

Copy the entire output — this is your public key.

Upload the Public Key to LightYear

1. Log in to the LightYear control panel.
2. Navigate to Account → SSH Keys.
3. Click Add SSH Key.
4. Paste your public key into the text field.
5. Enter a descriptive label (e.g., MacBook Pro 2024).
6. Click Save.

The key is now available to select when deploying new servers.

Add a Key to an Existing Server

If you need to add a key to a server that is already running:

$ssh-copy-id -i ~/.ssh/id_ed25519.pub root@YOUR_SERVER_IP

Or manually append the public key:

$echo "YOUR_PUBLIC_KEY" >> ~/.ssh/authorized_keys
$chmod 600 ~/.ssh/authorized_keys

[!IMPORTANT] Always test the new key in a second terminal session before closing your existing session. This prevents being locked out if the key was not added correctly.