Your First 30 Minutes on a Linux Server

You've just deployed a fresh Linux server. The next 30 minutes are critical — this is when you'll establish the security baseline and basic configuration that everything else builds on. Follow this guide step by step to set up a secure, well-configured server.

Minute 0-5: Connect and Update

Connect via SSH

# Connect to your server (replace with your IP)
ssh root@YOUR_SERVER_IP

# If you get a host key warning on first connect, verify the fingerprint
# then type "yes" to continue

Update the System

# Ubuntu/Debian
apt update && apt upgrade -y

# AlmaLinux/Rocky
dnf update -y

Minute 5-10: Create a Non-Root User

Running everything as root is dangerous — a single mistake can destroy your system. Create a regular user with sudo privileges.

# Create a new user
adduser deploy

# Add to sudo group (Ubuntu/Debian)
usermod -aG sudo deploy

# Or for AlmaLinux/Rocky
usermod -aG wheel deploy

# Test the new user
su - deploy
sudo whoami
# Should output: root

Minute 10-15: Secure SSH

Set Up SSH Keys

# On your LOCAL machine, generate a key pair (if you don't have one)
ssh-keygen -t ed25519 -C "your_email@example.com"

# Copy your public key to the server
ssh-copy-id deploy@YOUR_SERVER_IP

# Test key-based login
ssh deploy@YOUR_SERVER_IP

Harden SSH Configuration

# On the server, edit SSH config
sudo nano /etc/ssh/sshd_config

# Make these changes:
PermitRootLogin no
PasswordAuthentication no
PubkeyAuthentication yes
MaxAuthTries 3
ClientAliveInterval 300
ClientAliveCountMax 2
X11Forwarding no
AllowUsers deploy

# Restart SSH (keep your current session open!)
sudo systemctl restart sshd

# TEST: Open a NEW terminal and verify you can still log in
ssh deploy@YOUR_SERVER_IP

Minute 15-20: Set Up the Firewall

# Ubuntu/Debian with UFW
sudo ufw default deny incoming
sudo ufw default allow outgoing
sudo ufw allow ssh
sudo ufw allow 80/tcp
sudo ufw allow 443/tcp
sudo ufw enable

# Verify rules
sudo ufw status verbose

# AlmaLinux/Rocky with firewalld
sudo systemctl enable --now firewalld
sudo firewall-cmd --permanent --add-service=ssh
sudo firewall-cmd --permanent --add-service=http
sudo firewall-cmd --permanent --add-service=https
sudo firewall-cmd --reload
sudo firewall-cmd --list-all

Minute 20-25: Configure Basics

Set the Hostname

sudo hostnamectl set-hostname myserver
echo "127.0.0.1 myserver" | sudo tee -a /etc/hosts

Set the Timezone

# List available timezones
timedatectl list-timezones | grep America

# Set your timezone
sudo timedatectl set-timezone America/New_York

# Enable NTP time synchronization
sudo timedatectl set-ntp true

Install Essential Tools

# Ubuntu/Debian
sudo apt install -y curl wget git htop vim unzip net-tools

# AlmaLinux/Rocky
sudo dnf install -y curl wget git htop vim unzip net-tools

Minute 25-30: Set Up Automatic Security Updates

# Ubuntu/Debian — unattended-upgrades
sudo apt install -y unattended-upgrades
sudo dpkg-reconfigure -plow unattended-upgrades

# Verify it's enabled
cat /etc/apt/apt.conf.d/20auto-upgrades
# APT::Periodic::Update-Package-Lists "1";
# APT::Periodic::Unattended-Upgrade "1";

# AlmaLinux/Rocky — dnf-automatic
sudo dnf install -y dnf-automatic
sudo systemctl enable --now dnf-automatic-install.timer

Post-Setup Verification Checklist

# Run these checks to verify your setup:

# 1. Can you log in as your non-root user with SSH key?
ssh deploy@YOUR_SERVER_IP

# 2. Is root login disabled?
ssh root@YOUR_SERVER_IP  # Should fail

# 3. Is the firewall active?
sudo ufw status  # or sudo firewall-cmd --list-all

# 4. Is the system up to date?
sudo apt list --upgradable  # Should show nothing

# 5. Is NTP synced?
timedatectl status | grep "synchronized"

# 6. Are automatic updates enabled?
systemctl status unattended-upgrades  # Ubuntu
systemctl status dnf-automatic-install.timer  # RHEL

What to Do Next

With these basics in place, your next steps should be:

1. Install and configure your web server (Nginx or Apache)
2. Set up SSL certificates with Let's Encrypt
3. Configure automated backups
4. Install application-specific software (databases, runtimes)
5. Set up monitoring and alerting

Check our other Getting Started guides for detailed walkthroughs of each step.