Accessing Virtual Machine (SSH)


Generate SSH Key

Here are step-by-step instructions to generate an SSH key on both Windows and Mac systems:

For Windows (Windows 10/11):

  1. Ensure OpenSSH Client is Installed

    • Open Settings > Apps > Apps & Features > Optional Features.
    • Check if OpenSSH Client is listed.
    • If not, click Add a feature, find OpenSSH Client, and install it.
    • Restart your computer if needed.

  2. Open Command Prompt or PowerShell

    • Press Windows + R, type cmd or powershell, and press Enter.

  3. Generate SSH Key

    • Type the command: 
      ssh-keygen
    • Press Enter to accept the default save location (C:\Users\<username>\.ssh\id_rsa).

  4. Set a Passphrase (Optional)

    • When prompted, enter a passphrase for extra security, or just press Enter twice to skip.

  5. Complete

    • The keys are generated, usually two files: id_rsa (private key) and id_rsa.pub (public key) under .ssh folder in your user directory.

For Mac (macOS):

  1. Open Terminal

    • Find Terminal via Spotlight Search or in Applications > Utilities.

  2. Generate SSH Key

    • Run the command, replacing your email with your own: 
      ssh-keygen -t ed25519 -C "your_email@example.com"
    • If your macOS or server doesn't support Ed25519, use: 
      ssh-keygen -t rsa -b 4096 -C "your_email@example.com"

  3. Save Key Location

    • Press Enter to accept the default file location (/Users/you/.ssh/id_ed25519 or /Users/you/.ssh/id_rsa).

  4. Set a Passphrase (Optional)

    • Enter a secure passphrase or press Enter to leave it blank.

  5. Add SSH Key to ssh-agent

    • Start the ssh-agent: 
      eval "$(ssh-agent -s)"
    • Add your private key: 
      ssh-add -K ~/.ssh/id_ed25519
    • If using RSA: 
      ssh-add -K ~/.ssh/id_rsa

In both OS, your generated SSH public key is the one you copy and add to services like GitHub, servers, etc. The private key should remain secure and never shared.

Install Private Key (SSH)

Here are step-by-step instructions on how to store an SSH private key securely once generated on both Windows and Mac systems:

Windows

  1. Default Location

    • By default, SSH private keys are saved in your user profile directory under: 
      C:\Users\<your_username>\.ssh\
    • The private key file is usually named id_rsa or similar.

  2. Set File Permissions

    • Ensure only your user account has access to the private key file:
      • Right-click the private key file > Properties > Security tab.
      • Remove access for any other users or groups except yourself.

  3. Use SSH-Agent for Secure Key Storage

    • Open PowerShell as Administrator.
    • Enable and start the ssh-agent service: 
      Get-Service ssh-agent | Set-Service -StartupType Automatic
Start-Service ssh-agent
    • Add your private key to ssh-agent to avoid typing your passphrase every time: 
      ssh-add $env:USERPROFILE\.ssh\id_rsa
    • The ssh-agent stores your private keys encrypted, protected by your Windows user credentials.

  4. Backup Private Key Securely

    • Copy the private key file to an encrypted external drive or secure password manager.
    • Avoid storing private keys in shared or non-encrypted folders.
    • Do NOT share the private key.

Mac (macOS)

  1. Default Location

    • Private keys are stored in the hidden .ssh folder in your home directory: 
      ~/.ssh/id_rsa
    • Use ls -la ~/.ssh in Terminal to view.

  2. Set Proper File Permissions

    • Ensure your private key file is readable only by you: 
      chmod 600 ~/.ssh/id_rsa

  3. Add SSH Key to ssh-agent

    • Start the ssh-agent: 
      eval "$(ssh-agent -s)"
    • Add your private key with: 
      ssh-add -K ~/.ssh/id_rsa
    • This stores your key securely in the macOS keychain.

  4. Backup Private Key Safely

    • Store a copy on an encrypted USB drive or a password manager like 1Password.
    • Never upload your private key unencrypted to cloud storage.
    • Keep backups separate from your main machine to avoid loss.

Security best practices:

Access Virtual Machine (VM) using SSH Key (Windows / Macbook)

Here are step-by-step instructions to access a Server or Virtual Machine using SSH on both Windows and Mac:

Windows (Using PowerShell or Command Prompt)

  1. Ensure OpenSSH Client is Installed

    • Go to Settings > Apps > Optional Features.
    • Confirm OpenSSH Client is installed; if not, click Add a feature, find it, and install.

  2. Open PowerShell or Command Prompt

    • Press Windows + R, type powershell or cmd, and hit Enter.

  3. Connect via SSH

    • Use the command: 
      ssh username@server_ip
    • Replace username with your remote server username.
    • Replace server_ip with the server’s domain name or IP address.
    • If the server uses a non-standard port, add -p followed by the port number: 
      ssh username@server_ip -p port_number

  4. Verify and Accept Host Key

    • At first connection, you’ll be asked to verify the server’s fingerprint.
    • Type yes and press Enter to continue.

  5. Authenticate

    • Enter your password when prompted (or if using key authentication, make sure your private key is loaded or specify it with -i).

  6. You are connected when your prompt changes to the remote server’s shell.

Mac (Using Terminal)

  1. Open Terminal

    • Use Spotlight or find Terminal in Applications > Utilities.

  2. Connect via SSH

    • Type the command: 
      ssh username@server_ip
    • Substitute username and server_ip with appropriate remote account and server info.
    • For custom ports, add -p option: 
      ssh username@server_ip -p port_number

  3. Accept Host Key

    • For the first-time connection, review and accept the host key by typing yes.

  4. Authenticate

    • Enter your password or ensure your SSH private key is loaded (use ssh-add if needed).

  5. You are connected once you see the shell prompt of the remote server.

Additional Tips: