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.
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. 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. 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 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 "your-email@example.com"
Replace your-email@example.com 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 . 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 "your-email@example.com"
Replace your-email@example.com 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:
Open Settings → Apps → Optional Features
Click Add a feature
Search for OpenSSH Client and install it
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:
Download PuTTY (includes PuTTYgen)
Open PuTTYgen from the Start menu
Under “Type of key to generate”, select EdDSA and ensure Ed25519 is selected
Click Generate and move your mouse randomly in the window to create randomness
Once generated, the public key appears in the text box at the top — copy it
Click Save private key and save it somewhere safe on your computer
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.
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 "your-email@example.com"
Replace your-email@example.com 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
Log in to console.nova-cloud.ai
Go to Account Settings → SSH Keys
Click Add SSH Key
Paste your public key (the text you copied above — it starts with ssh-ed25519)
Enter a name to help you remember which computer this key is from (e.g., “MacBook Pro”, “Work Desktop”)
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-ed25519Ed25519 Yes — fastest, most securessh-rsaRSA (2048+ bit) Yes — widely compatible ecdsa-sha2-nistp256ECDSA 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
Windows (PowerShell)
Windows (PuTTY)
ssh ubuntu@ < your-vm-ip-addres s >
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. ssh ubuntu@ < your - vm - ip - address >
First time connecting? You’ll see a fingerprint confirmation prompt. Type yes and press Enter.If you generated your key with PuTTYgen:
Open PuTTY
In Host Name , enter: ubuntu@<your-vm-ip-address>
In the left panel, go to Connection → SSH → Auth → Credentials
Under “Private key file for authentication”, browse to your saved .ppk file
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-addres s >
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:
Go to Account Settings → SSH Keys
Click the delete button next to the key
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:
Make sure you uploaded the right key. The public key you uploaded to Nova Cloud must match the private key on your computer.
Specify the key explicitly:
ssh -i ~/.ssh/id_ed25519 ubuntu@ < vm-i p >
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
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:
Open Settings → Apps → Optional Features
Click Add a feature
Search for OpenSSH Client and install it
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.
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
If SSH hangs and eventually says “Connection timed out”:
Make sure the VM is in Running status in the dashboard
Check that you’re using the correct IP address from the dashboard
Wait a minute — newly created VMs may take a moment to be fully accessible
Try again. If it persists, the VM may be experiencing issues — try stopping and starting it from the dashboard.
