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<!DOCTYPE html>
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    <title>Adding Users via SSH on EC2</title>
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    <div class="presentation">
        <div class="slide-counter">
            <span id="current">1</span> / <span id="total">9</span>
        </div>

        <!-- Slide 1: Title -->
        <div class="slide active">
            <h1>☁️ Adding Users via SSH on EC2</h1>
            <p style="font-size: 1.5em; margin-top: 40px;">A Complete Guide to User Management</p>
            <div style="margin-top: 60px;">
                <p><span class="emoji">🔐</span> Secure SSH access</p>
                <p><span class="emoji">👥</span> Multiple user management</p>
                <p><span class="emoji">🔑</span> SSH key authentication</p>
                <p><span class="emoji">⚡</span> Best practices included</p>
            </div>
        </div>

        <!-- Slide 2: Prerequisites -->
        <div class="slide">
            <h2>📋 Prerequisites</h2>
            <p>Before you start, make sure you have:</p>

            <div class="step-box">
                <p><span class="step-number">1</span><strong>Running EC2 Instance</strong></p>
                <p style="margin-left: 45px;">Your EC2 instance should be up and running</p>
            </div>

            <div class="step-box">
                <p><span class="step-number">2</span><strong>SSH Access</strong></p>
                <p style="margin-left: 45px;">You can already connect to your EC2 instance via SSH</p>
            </div>

            <div class="step-box">
                <p><span class="step-number">3</span><strong>Root/Sudo Privileges</strong></p>
                <p style="margin-left: 45px;">You need sudo access to create users</p>
            </div>

            <div class="step-box">
                <p><span class="step-number">4</span><strong>Key Pair (Optional)</strong></p>
                <p style="margin-left: 45px;">SSH key for the new user (for key-based auth)</p>
            </div>
        </div>

        <!-- Slide 3: Connect to EC2 -->
        <div class="slide">
            <h2>🔌 Step 1: Connect to Your EC2</h2>

            <h3>For Amazon Linux / Ubuntu:</h3>
            <div class="code-box">
<span class="comment"># Amazon Linux</span>
ssh -i your-key.pem ec2-user@your-ec2-ip

<span class="comment"># Ubuntu</span>
ssh -i your-key.pem ubuntu@your-ec2-ip
            </div>

            <div class="info-box">
                <p><span class="emoji">💡</span> <strong>Tip:</strong> Replace <code>your-key.pem</code> with your actual key file name and <code>your-ec2-ip</code> with your instance's public IP or DNS.</p>
            </div>

            <div class="warning-box">
                <p><span class="emoji">⚠️</span> <strong>Permission Error?</strong> Run: <code>chmod 400 your-key.pem</code></p>
            </div>
        </div>

        <!-- Slide 4: Create New User -->
        <div class="slide">
            <h2>👤 Step 2: Create a New User</h2>

            <h3>Basic user creation:</h3>
            <div class="code-box">
<span class="comment"># Create a new user named 'john'</span>
sudo adduser john

<span class="comment"># You'll be prompted to set a password and user details</span>
<span class="comment"># Press Enter to skip optional fields</span>
            </div>

            <h3>What happens:</h3>
            <ul>
                <li>Creates a new user account</li>
                <li>Creates a home directory: <code>/home/john</code></li>
                <li>Sets up basic user configuration</li>
                <li>Prompts for password (if using password auth)</li>
            </ul>

            <div class="info-box">
                <p><span class="emoji">📝</span> <strong>Alternative:</strong> Use <code>sudo useradd john</code> for basic user creation without prompts, then set password with <code>sudo passwd john</code></p>
            </div>
        </div>

        <!-- Slide 5: Grant Sudo Access -->
        <div class="slide">
            <h2>⚡ Step 3: Grant Sudo Access (Optional)</h2>

            <p>If the new user needs administrative privileges:</p>

            <h3>Method 1: Add to sudo group</h3>
            <div class="code-box">
<span class="comment"># Amazon Linux / Ubuntu</span>
sudo usermod -aG sudo john

<span class="comment"># CentOS / RHEL</span>
sudo usermod -aG wheel john
            </div>

            <h3>Method 2: Edit sudoers file</h3>
            <div class="code-box">
<span class="comment"># Open sudoers file safely</span>
sudo visudo

<span class="comment"># Add this line at the end:</span>
john ALL=(ALL) NOPASSWD:ALL
            </div>

            <div class="warning-box">
                <p><span class="emoji">⚠️</span> <strong>Warning:</strong> <code>NOPASSWD</code> allows sudo without password. Remove it if you want password prompts for sudo commands.</p>
            </div>
        </div>

        <!-- Slide 6: Setup SSH Key Auth -->
        <div class="slide">
            <h2>🔑 Step 4: Setup SSH Key Authentication</h2>

            <h3>Option A: Generate key on local machine</h3>
            <div class="code-box">
<span class="comment"># On your local computer</span>
ssh-keygen -t rsa -b 4096 -C "john@company.com"

<span class="comment"># Save as: john_ec2_key</span>
<span class="comment"># This creates john_ec2_key (private) and john_ec2_key.pub (public)</span>
            </div>

            <h3>Option B: Copy existing public key</h3>
            <div class="code-box">
<span class="comment"># View your public key</span>
cat ~/.ssh/id_rsa.pub

<span class="comment"># Copy the output</span>
            </div>

            <div class="info-box">
                <p><span class="emoji">💡</span> <strong>Best Practice:</strong> Always use SSH key authentication instead of passwords for better security!</p>
            </div>
        </div>

        <!-- Slide 7: Add SSH Key to User -->
        <div class="slide">
            <h2>🔐 Step 5: Add SSH Key to New User</h2>

            <div class="code-box">
<span class="comment"># Switch to the new user</span>
sudo su - john

<span class="comment"># Create .ssh directory</span>
mkdir -p ~/.ssh
chmod 700 ~/.ssh

<span class="comment"># Create authorized_keys file</span>
touch ~/.ssh/authorized_keys
chmod 600 ~/.ssh/authorized_keys

<span class="comment"># Add public key (paste the public key content)</span>
nano ~/.ssh/authorized_keys
<span class="comment"># Paste the public key, save and exit (Ctrl+X, Y, Enter)</span>

<span class="comment"># Exit back to your original user</span>
exit
            </div>

            <div class="warning-box">
                <p><span class="emoji">⚠️</span> <strong>Critical:</strong> Permissions must be exact!<br>
                <code>~/.ssh</code> must be 700<br>
                <code>~/.ssh/authorized_keys</code> must be 600</p>
            </div>
        </div>

        <!-- Slide 8: Test New User -->
        <div class="slide">
            <h2>✅ Step 6: Test the New User</h2>

            <h3>From your local machine:</h3>
            <div class="code-box">
<span class="comment"># Test SSH connection with the new user</span>
ssh -i john_ec2_key john@your-ec2-ip

<span class="comment"># Or if using default key</span>
ssh john@your-ec2-ip
            </div>

            <h3>If successful, you should see:</h3>
            <div class="code-box">
<span class="prompt">john@ip-xxx-xx-xx-xx:~$</span>
            </div>

            <h3>Test sudo access (if granted):</h3>
            <div class="code-box">
<span class="comment"># Try a sudo command</span>
sudo apt update

<span class="comment"># Should work without errors</span>
            </div>

            <div class="info-box">
                <p><span class="emoji">🎉</span> <strong>Success!</strong> Your new user is ready to use!</p>
            </div>
        </div>

        <!-- Slide 9: Security Best Practices -->
        <div class="slide">
            <h2>🔒 Security Best Practices</h2>

            <div class="method-card">
                <h3>1. Disable Password Authentication</h3>
                <div class="code-box">
sudo nano /etc/ssh/sshd_config

<span class="comment"># Set these values:</span>
PasswordAuthentication no
PubkeyAuthentication yes

<span class="comment"># Restart SSH service</span>
sudo systemctl restart sshd
                </div>
            </div>

            <div class="method-card">
                <h3>2. Disable Root Login</h3>
                <div class="code-box">
<span class="comment"># In /etc/ssh/sshd_config</span>
PermitRootLogin no
                </div>
            </div>

            <div class="method-card">
                <h3>3. Other Tips</h3>
                <ul>
                    <li>Use strong SSH keys (4096-bit RSA or Ed25519)</li>
                    <li>Regularly update your EC2 instance</li>
                    <li>Use Security Groups to restrict SSH access to specific IPs</li>
                    <li>Enable AWS CloudTrail for auditing</li>
                    <li>Consider using AWS Systems Manager Session Manager</li>
                </ul>
            </div>
        </div>

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