Installing Ubuntu Server Step-by-Step

Installing Ubuntu Server Step by Step

Installing Ubuntu Server is straightforward, but several decisions during the install — partitioning scheme, storage layout, whether to enable LVM — have long-term consequences that are hard to undo. This guide walks through every step of a fresh Ubuntu 24.04 LTS Server installation with the choices that work in production.

Pre-installation checklist

Before you touch the installer, confirm these items. Installing on the wrong disk or with the wrong network settings means starting over.

If installing on a VM, create the VM with enough disk space now — expanding a disk after installation with LVM is possible but adds steps. For physical servers, note which disk is the target (/dev/sda, /dev/nvme0n1, etc.) before booting the installer.

Download and verify the ISO

Always verify the ISO before writing it to USB. A corrupt download causes cryptic installation failures mid-process.

# On your workstation, after downloading the ISO
# Check the SHA256 hash against the value on ubuntu.com/download/server
sha256sum ubuntu-24.04.1-live-server-amd64.iso

Expected output (compare to ubuntu.com)

e240e4b801f7bb68c20d1356b60968ad0c33a41d00d828e74ceb3364a0317be  ubuntu-24.04.1-live-server-amd64.iso

If the hash does not match exactly, delete the file and re-download it.

Create a bootable USB

On Linux or macOS, use dd. On Windows, use Balena Etcher (free download).

# On Linux/macOS — find your USB device first
lsblk
# or on macOS: diskutil list

# Write the ISO to the USB drive
# WARNING: Replace /dev/sdX with YOUR USB device. This will erase the entire drive.
sudo dd if=ubuntu-24.04.1-live-server-amd64.iso of=/dev/sdX bs=4M status=progress conv=fsync

⚠️ WARNING: The dd command will immediately and silently overwrite everything on the target device. Double-check the device name (lsblk output) before running this command. Writing to the wrong device destroys data with no undo.

Boot from USB and start the installer

Insert the USB drive and power on the machine. Enter the boot menu (usually F12, F10, or DEL depending on the manufacturer) and select the USB drive. The Ubuntu Server installer (Subiquity) loads within a few seconds and presents a text-based interface.

At the first screen, select Try or Install Ubuntu Server. Ignore the HWE option unless you have specific hardware that requires a newer kernel.

Language, keyboard, and network

1. Language: Select English unless you have a specific reason to change it. Server log files and documentation are predominantly in English, and selecting another language can cause issues with log parsing tools.
2. Keyboard layout: Select your physical keyboard layout. The default is English (US).
3. Installation type: Select Ubuntu Server (not Minimized). Minimized removes manpages and debugging tools you will need later.
4. Network: The installer lists all detected network interfaces. If your server needs a static IP, press Enter on the interface, select Edit IPv4, change to Manual, and enter:
   • Subnet: e.g., 192.168.1.0/24
   • Address: e.g., 192.168.1.50
   • Gateway: e.g., 192.168.1.1
   • DNS: e.g., 8.8.8.8,8.8.4.4
5. Proxy: Leave blank unless your network requires an HTTP proxy to reach the internet.
6. Mirror: The installer will test the default mirror. Accept it unless you need a regional mirror for speed.

Storage partitioning

This is the most important decision in the installation. The default option is Use an entire disk with LVM, which is the right choice for most servers. LVM lets you resize partitions and add disks later without reinstalling.

For a production server, the custom layout is best practice because it prevents a full /var/log from making the root filesystem read-only. A common production layout:

Disk: /dev/sda (50 GB)
├── /dev/sda1    1 GB    EFI System Partition (FAT32)
├── /dev/sda2    2 GB    /boot (ext4)
└── /dev/sda3    47 GB   LVM Physical Volume
    └── ubuntu-vg (Volume Group)
        ├── ubuntu-lv-root  20 GB   / (ext4)
        ├── ubuntu-lv-var   15 GB   /var (ext4)
        ├── ubuntu-lv-home   5 GB   /home (ext4)
        └── ubuntu-lv-swap   2 GB   swap

If you are installing in a VM for learning, accepting the default LVM layout is fine.

⚠️ WARNING: The Erase disk and install Ubuntu step is the point of no return. If this is an existing system with data, verify you have selected the correct disk before confirming.

User account and OpenSSH

1. Profile setup: Enter your full name, a server name (hostname), a username, and a password. The username will be your default SSH login. Choose a strong password — you will use it for sudo on this server.
2. Ubuntu Pro: Skip this screen for now (select Skip for now). You can attach Ubuntu Pro after installation with sudo pro attach.
3. OpenSSH server: Select Install OpenSSH server. This is essential. Without it, you cannot SSH into the server after installation.
4. Snap packages: Skip the featured snaps screen unless you specifically need one. Most services are installed via apt.

Wait for installation to complete

The installer copies files to disk, installs the bootloader, and runs first-boot configuration. This takes 5–15 minutes depending on disk speed. When the installation completes, you will see a Reboot Now option. Select it, and remove the USB drive when prompted.

First steps after installation

After the server boots and you log in (either at the console or via SSH), run these steps immediately:

# 1. Update the package list and apply all security updates
# This is critical — the ISO may be months old
sudo apt update && sudo apt upgrade -y

# 2. Verify the installation details
lsb_release -a          # Confirm Ubuntu version
uname -r                # Confirm kernel version
hostname                # Confirm the hostname you set
ip a                    # Confirm network interface and IP address

# 3. Confirm SSH is running and will start at boot
systemctl status ssh
systemctl is-enabled ssh

# 4. Check disk layout
lsblk
df -h

# 5. Verify sudo works for your user
sudo whoami             # Should print: root

Example output of ip a on a fresh server

2: ens3: <BROADCAST,MULTICAST,UP,LOWER_UP>
    inet 192.168.1.50/24 brd 192.168.1.255 scope global ens3

After these checks, your server is ready. Next steps are typically: configuring a firewall (UFW), setting up automatic security updates, and installing your application stack.

Conclusion

Ubuntu Server installation is mostly about the decisions you make before clicking “install”: the right ISO, verified checksum, correct disk target, LVM for flexibility, and OpenSSH enabled. After installation, immediately run sudo apt update && sudo apt upgrade before doing anything else — the ISO you installed from may be months old.