SSH Keys

Generate and manage SSH keys for secure access to your Nova Cloud VMs.

SSH keys let you securely connect to your Nova Cloud virtual machines without needing a password. This guide walks you through everything step by step — even if you’ve never used SSH before.

What Are SSH Keys?

SSH keys work like a digital lock-and-key system:

• Private key — Stays on your computer. Think of this as your house key — never share it.
• Public key — You upload this to Nova Cloud. Think of this as the lock on your door.

When you connect to a VM, your computer proves it has the matching private key. No password is sent over the internet, making it much more secure than password authentication.

Do I Already Have an SSH Key?

Before generating a new key, check if you already have one.

Mac

Open Terminal (search for “Terminal” in Spotlight, or find it in Applications → Utilities) and run:

ls ~/.ssh/id_ed25519.pub 2>/dev/null && echo "Key found!" || echo "No key found."

If you see “Key found!”, skip to Upload Your Key. Otherwise, follow the generation steps below.

Windows

Open PowerShell (search for “PowerShell” in the Start menu) and run:

if (Test-Path "$env:USERPROFILE\.ssh\id_ed25519.pub") { "Key found!" } else { "No key found." }

If you see “Key found!”, skip to Upload Your Key. Otherwise, follow the generation steps below.

Linux

Open a terminal and run:

ls ~/.ssh/id_ed25519.pub 2>/dev/null && echo "Key found!" || echo "No key found."

If you see “Key found!”, skip to Upload Your Key. Otherwise, follow the generation steps below.

Generating a New SSH Key

Mac

Step 1: Open Terminal

• Press Cmd + Space to open Spotlight
• Type Terminal and press Enter

Step 2: Generate the Key

Paste this command and press Enter:

ssh-keygen -t ed25519 -C "[e-mail]"

Replace [e-mail] with your actual email (this is just a label to help you identify the key).

Step 3: Save the Key

You’ll see:

Enter file in which to save the key (/Users/yourname/.ssh/id_ed25519):

Just press Enter to accept the default location.

Step 4: Set a Passphrase (Optional)

You’ll be asked for a passphrase. You have two options:

• Press Enter twice for no passphrase (simpler, fine for most users)
• Type a passphrase for extra security (you’ll need to enter it each time you connect)

Step 5: Copy Your Public Key

pbcopy < ~/.ssh/id_ed25519.pub

This copies the key to your clipboard silently — you won’t see any output. Your key is ready to paste into the Nova Cloud console.

If pbcopy doesn’t work, you can display the key and copy it manually:

cat ~/.ssh/id_ed25519.pub

Select the entire output (it starts with ssh-ed25519) and copy it with Cmd + C.

Windows

Step 1: Open PowerShell

• Click the Start button or press the Windows key
• Type PowerShell and click to open it

Step 2: Generate the Key

Paste this command and press Enter:

ssh-keygen -t ed25519 -C "[e-mail]"

Replace [e-mail] with your actual email.

Windows 10 (version 1809+) and Windows 11 include SSH tools by default. If you see an error like “ssh-keygen is not recognized”, you need to enable the OpenSSH Client:

1. Open Settings → Apps → Optional Features
2. Click Add a feature
3. Search for OpenSSH Client and install it
4. Close and re-open PowerShell, then try again

Step 3: Save the Key

You’ll see:

Enter file in which to save the key (C:\Users\YourName\.ssh\id_ed25519):

Just press Enter to accept the default location.

Step 4: Set a Passphrase (Optional)

You’ll be asked for a passphrase. You have two options:

• Press Enter twice for no passphrase (simpler, fine for most users)
• Type a passphrase for extra security (you’ll need to enter it each time you connect)

Step 5: Copy Your Public Key

Get-Content $env:USERPROFILE\.ssh\id_ed25519.pub | Set-Clipboard

This copies the key to your clipboard. Your key is ready to paste into the Nova Cloud console.

If the clipboard command doesn’t work, you can display the key and copy it manually:

Get-Content $env:USERPROFILE\.ssh\id_ed25519.pub

Select the entire output (it starts with ssh-ed25519) and copy it with Ctrl + C.

Alternative: PuTTYgen (Older Windows Systems)

If you’re on an older version of Windows without built-in SSH:

1. Download PuTTY (includes PuTTYgen)
2. Open PuTTYgen from the Start menu
3. Under “Type of key to generate”, select EdDSA and ensure Ed25519 is selected
4. Click Generate and move your mouse randomly in the window to create randomness
5. Once generated, the public key appears in the text box at the top — copy it
6. Click Save private key and save it somewhere safe on your computer
7. Paste the public key into the Nova Cloud console

If you use PuTTYgen, you’ll need to use PuTTY (not the built-in ssh command) to connect to your VMs. For most Windows 10/11 users, the PowerShell method above is simpler.

Linux

Step 1: Open a Terminal

Use your distribution’s terminal application (e.g., GNOME Terminal, Konsole, xterm).

Step 2: Generate the Key

ssh-keygen -t ed25519 -C "[e-mail]"

Replace [e-mail] with your actual email.

Step 3: Save the Key

Press Enter to accept the default location (~/.ssh/id_ed25519).

Step 4: Set a Passphrase (Optional)

Press Enter twice for no passphrase, or type one for extra security.

Step 5: Copy Your Public Key

cat ~/.ssh/id_ed25519.pub

Select and copy the entire output line (it starts with ssh-ed25519).

If you have xclip or wl-copy installed, you can copy directly to the clipboard:

# X11
xclip -selection clipboard < ~/.ssh/id_ed25519.pub
# Wayland
wl-copy < ~/.ssh/id_ed25519.pub

Uploading Your SSH Key

1. Log in to console.nova-cloud.ai
2. Go to Account Settings → SSH Keys
3. Click Add SSH Key
4. Paste your public key (the text you copied above — it starts with ssh-ed25519)
5. Enter a name to help you remember which computer this key is from (e.g., “MacBook Pro”, “Work Desktop”)
6. Click Save

You can upload up to 5 SSH keys per account. This is useful if you connect from multiple computers.

Supported Key Types

Key Type	Algorithm	Recommended?
ssh-ed25519	Ed25519	Yes — fastest, most secure
ssh-rsa	RSA (2048+ bit)	Yes — widely compatible
ecdsa-sha2-nistp256	ECDSA P-256	Supported

We recommend Ed25519 for the best combination of security and performance. The instructions on this page generate Ed25519 keys by default.

Connecting to a VM

Once your VM is running (you can see the status on the Dashboard), connect using the IP address shown in the console:

Mac / Linux

ssh ubuntu@<your-vm-ip-address>

First time connecting? You’ll see a message like:

The authenticity of host '...' can't be established.
Are you sure you want to continue connecting (yes/no)?

Type yes and press Enter. This is normal and only happens once per VM.

Windows (PowerShell)

ssh ubuntu@<your-vm-ip-address>

First time connecting? You’ll see a fingerprint confirmation prompt. Type yes and press Enter.

Windows (PuTTY)

If you generated your key with PuTTYgen:

1. Open PuTTY
2. In Host Name, enter: ubuntu@<your-vm-ip-address>
3. In the left panel, go to Connection → SSH → Auth → Credentials
4. Under “Private key file for authentication”, browse to your saved .ppk file
5. Click Open to connect

Specifying a Key Manually

If you have multiple SSH keys, you can tell SSH which one to use:

ssh -i ~/.ssh/id_ed25519 ubuntu@<your-vm-ip-address>

Managing Your Keys

Viewing Keys

See all your uploaded keys in Account Settings → SSH Keys. Each key shows its name, type, fingerprint, and when it was added.

Deleting a Key

To remove a key you no longer need:

1. Go to Account Settings → SSH Keys
2. Click the delete button next to the key
3. Confirm the deletion

Deleting a key from your account does not remove it from VMs that are already running. It only prevents the key from being added to new VMs.

Troubleshooting

Permission denied (publickey)

This means the VM doesn’t recognize your key. Try these fixes:

1. Make sure you uploaded the right key. The public key you uploaded to Nova Cloud must match the private key on your computer.

2. Specify the key explicitly:

ssh -i ~/.ssh/id_ed25519 ubuntu@<vm-ip>

3. Check your SSH agent:

# See which keys are loaded
ssh-add -l

# If your key isn't listed, add it
ssh-add ~/.ssh/id_ed25519

4. Check file permissions (Mac/Linux): Your private key file must not be readable by others:

chmod 600 ~/.ssh/id_ed25519

ssh command not found (Windows)

Windows 10 (version 1809+) and Windows 11 include an SSH client, but it may not be enabled:

1. Open Settings → Apps → Optional Features
2. Click Add a feature
3. Search for OpenSSH Client and install it
4. Restart PowerShell and try again

Alternatively, use PuTTY as described above.

Key format not recognized

Make sure you’re uploading the public key (ending in .pub), not the private key. The public key should be a single line starting with ssh-ed25519, ssh-rsa, or ecdsa-sha2-nistp256.

Maximum keys reached

You can have up to 5 SSH keys per account. Delete unused keys in Account Settings → SSH Keys before adding new ones.

Key works for some VMs but not others

SSH keys are added to a VM when it’s created. If you uploaded a new key after creating a VM, that key won’t be on the existing VM.

Solutions:

• Create a new VM (it will include your latest keys)
• Or manually add the key inside the running VM:

echo "ssh-ed25519 AAAA..." >> ~/.ssh/authorized_keys

Connection times out

If SSH hangs and eventually says “Connection timed out”:

1. Make sure the VM is in Running status in the dashboard
2. Check that you’re using the correct IP address from the dashboard
3. Wait a minute — newly created VMs may take a moment to be fully accessible
4. Try again. If it persists, the VM may be experiencing issues — try stopping and starting it from the dashboard.