Set Up SSH Keys

Why SSH Keys?

SSH keys are more secure than passwords:

Password	SSH Key
Can be guessed	Virtually uncrackable
Brute-force possible	Brute-force impossible
Must be entered manually	Automatic authentication
Can be intercepted	Private key stays local

After setup, you can connect without entering a password - faster and more secure!

Create SSH Key

Windows
macOS
Linux

Windows 10/11 (PowerShell)

Open PowerShell

Press Win + X and select Windows Terminal or PowerShell.

Generate SSH Key

ssh-keygen -t ed25519 -C "your@email.com"

ED25519 is the most modern and secure algorithm. If your server doesn’t support it, use RSA:

ssh-keygen -t rsa -b 4096 -C "your@email.com"

Confirm Location

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

Press Enter for the default location.

Set Passphrase (recommended)

Enter passphrase (empty for no passphrase):

A passphrase adds extra protection to your key. You can also press Enter for no passphrase.

Copy Public Key

cat ~/.ssh/id_ed25519.pub

Copy the entire output (starts with ssh-ed25519).

PuTTYgen (Alternative)

Open PuTTYgen

Install PuTTY and open PuTTYgen.

Generate Key

Select EdDSA (or RSA with 4096 bits)
Click Generate
Move your mouse in the empty area for randomness

Save Keys

Save private key → Save as .ppk file
Copy the text in the upper field (Public Key)

Terminal

Open Terminal

Cmd + Space → “Terminal”

Generate SSH Key

ssh-keygen -t ed25519 -C "your@email.com"

Location and Passphrase

Enter for default location (~/.ssh/id_ed25519)
Optional: Enter a passphrase

Add Key to SSH Agent

eval "$(ssh-agent -s)"
ssh-add ~/.ssh/id_ed25519

For persistent storage, add to ~/.ssh/config:

Host *
  AddKeysToAgent yes
  UseKeychain yes
  IdentityFile ~/.ssh/id_ed25519

Copy Public Key

cat ~/.ssh/id_ed25519.pub | pbcopy

The key is now in your clipboard.

Terminal

Generate SSH Key

ssh-keygen -t ed25519 -C "your@email.com"

Location and Passphrase

Enter for default location
Optional: Passphrase for extra security

Add Key to SSH Agent

eval "$(ssh-agent -s)"
ssh-add ~/.ssh/id_ed25519

Display Public Key

cat ~/.ssh/id_ed25519.pub

Copy the output.

Add Public Key to Server

Now you need to add your Public Key to the server.

Method 1: ssh-copy-id (recommended)

The easiest way - works on macOS and Linux:

ssh-copy-id root@YOUR-IP-ADDRESS

You’ll be asked for the password once. After that, the key is set up.

Method 2: Manual Copy

ssh root@YOUR-IP-ADDRESS

Create SSH Directory (if needed)

mkdir -p ~/.ssh
chmod 700 ~/.ssh

Add Public Key

echo "YOUR-PUBLIC-KEY-HERE" >> ~/.ssh/authorized_keys
chmod 600 ~/.ssh/authorized_keys

Replace YOUR-PUBLIC-KEY-HERE with the copied key (starts with ssh-ed25519 or ssh-rsa).

Test Connection

Open a new terminal and connect:

ssh root@YOUR-IP-ADDRESS

If there’s no password prompt, the key works!

First test that your SSH key works! Otherwise you’ll lock yourself out.

After successful key setup, you can disable password login:

Edit SSH Configuration

nano /etc/ssh/sshd_config

Change Settings

Find and change these lines:

PasswordAuthentication no
PubkeyAuthentication yes

Use Ctrl + W in nano to search.

Restart SSH Service

systemctl restart sshd

Test in New Terminal

Open a new terminal (keep the old one open!) and test:

ssh root@YOUR-IP-ADDRESS

If it works, you can close the old terminal.

Manage Multiple Keys

SSH Config File

For multiple servers with different keys, create ~/.ssh/config:

# RDP.sh Production Server
Host rdp-prod
    HostName 185.193.xxx.xxx
    User root
    IdentityFile ~/.ssh/id_ed25519

# RDP.sh Development Server
Host rdp-dev
    HostName 185.193.yyy.yyy
    User root
    IdentityFile ~/.ssh/id_ed25519_dev
    Port 2222

# Other Provider
Host other-server
    HostName example.com
    User admin
    IdentityFile ~/.ssh/other_key

Now you can simply connect with:

ssh rdp-prod
ssh rdp-dev

Troubleshooting

Permission denied (publickey)

Possible causes:

Public key not copied correctly
Wrong permissions on server
Wrong key being used

Solution:

# Check permissions on server
chmod 700 ~/.ssh
chmod 600 ~/.ssh/authorized_keys

# Check which key is being used
ssh -v root@YOUR-IP

Agent has no identities

The SSH agent has no key loaded.Solution:

ssh-add ~/.ssh/id_ed25519

Key not accepted

Check on server:

cat ~/.ssh/authorized_keys

The key must be on a single line and start with ssh-ed25519 or ssh-rsa.

Forgot passphrase

Unfortunately, the passphrase cannot be recovered.Solution:

Generate a new key
Add the new public key to the server
Delete the old key

Best Practices

🔐 Use a Passphrase

A passphrase protects your key if someone gains access to your computer.

🔄 Rotate Keys

Regularly create new keys and remove old ones from authorized_keys.

💾 Backup

Back up your private key in a secure location. Without it, you’ll lose access!

🚫 Never Share

Never share your private key. Only the public key is copied to servers.

Next Steps

Configure Firewall

Protect your server with firewall rules

API Reference

Automate with our REST API

Documentation

Getting Started

FAQ

Why SSH Keys?

Create SSH Key

Windows 10/11 (PowerShell)

PuTTYgen (Alternative)

Terminal

Terminal

Add Public Key to Server

Method 1: ssh-copy-id (recommended)

Method 2: Manual Copy

Manage Multiple Keys

SSH Config File

Troubleshooting

Best Practices

🔐 Use a Passphrase

🔄 Rotate Keys

💾 Backup

🚫 Never Share

Next Steps

Configure Firewall

API Reference

​Why SSH Keys?

​Create SSH Key

​Windows 10/11 (PowerShell)

​PuTTYgen (Alternative)

​Terminal

​Terminal

​Add Public Key to Server

​Method 1: ssh-copy-id (recommended)

​Method 2: Manual Copy

​Disable Password Login

​Manage Multiple Keys

​SSH Config File

​Troubleshooting

​Best Practices

🔐 Use a Passphrase

🔄 Rotate Keys

💾 Backup

🚫 Never Share

​Next Steps

Configure Firewall

API Reference

Why SSH Keys?

Create SSH Key

Windows 10/11 (PowerShell)

PuTTYgen (Alternative)

Terminal

Terminal

Add Public Key to Server

Method 1: ssh-copy-id (recommended)

Method 2: Manual Copy

Disable Password Login

Manage Multiple Keys

SSH Config File

Troubleshooting

Best Practices

Next Steps