Installing Ubuntu Server 21.04 via USB is one of those projects that sounds intimidating until you actually do it. Then it becomes a very practical ritual: download an ISO, flash it to a USB drive, boot from it, answer a few installer questions, and suddenly your spare machine has transformed from “that dusty box under the desk” into a proper Linux server. Very dramatic. Very useful.
This guide walks you through the complete process of installing Ubuntu Server 21.04 via USB, from preparing the bootable drive to finishing the first login. Because Ubuntu Server 21.04, also known as Hirsute Hippo, is no longer supported, this tutorial is best for learning, labs, legacy testing, or rebuilding an older environment. For production servers, a current Ubuntu LTS release is the smarter choice because it receives long-term security updates.
Still, if your goal is to install Ubuntu Server 21.04 specifically, this article gives you a clear, practical, beginner-friendly roadmap. Bring a USB drive, a little patience, and maybe coffee. Servers respect coffee.
What You Need Before Installing Ubuntu Server 21.04
Before you start clicking buttons like a caffeinated sysadmin, make sure you have the right tools. The installation itself is straightforward, but preparation saves you from the classic “why is my USB not booting?” mystery drama.
Basic Requirements
You will need a computer or server where Ubuntu Server will be installed, a USB flash drive, the Ubuntu Server 21.04 ISO file, and software to create a bootable USB installer. An 8 GB USB drive is recommended, even if the ISO itself is smaller, because it gives you enough space and avoids compatibility problems with older tools.
The target machine should be compatible with the 64-bit AMD64 architecture, which covers most modern Intel and AMD desktops, laptops, mini PCs, and servers. You also need a keyboard, monitor, and network connection during installation. Ethernet is strongly recommended because Ubuntu Server installations are usually smoother when the machine has a wired connection.
Important Warning About Ubuntu Server 21.04
Ubuntu Server 21.04 reached end of life in January 2022. That means it no longer receives normal security updates from Canonical. If you are installing it for a home lab, software compatibility test, historical environment, or educational purpose, that is fine. If you are installing a public-facing web server, database server, file server, or business system, use a supported Ubuntu LTS version instead.
Think of Ubuntu 21.04 like a vintage motorcycle: fun to restore, educational to study, but probably not what you want for your daily emergency ambulance.
Step 1: Download the Ubuntu Server 21.04 ISO
Since Ubuntu Server 21.04 is no longer part of the current standard download page, you usually need to find it in Ubuntu’s old release archive. Look for the Ubuntu 21.04 Hirsute Hippo server install image. The file name usually follows a pattern similar to:
The “live-server” part means it uses Ubuntu’s modern server installer. The “amd64” part means it is for standard 64-bit Intel and AMD systems. Do not let the name confuse you: “amd64” does not mean it only works on AMD processors. It also works on compatible Intel 64-bit machines.
After downloading the ISO, save it somewhere easy to find, such as your Downloads folder. If checksum files are available, verify the ISO before flashing it. This extra step helps confirm that the download is complete and has not been corrupted. It is not glamorous, but neither is spending an hour troubleshooting a broken installer because the ISO downloaded like a soggy sandwich.
Step 2: Create a Bootable Ubuntu Server USB
Creating a bootable USB means writing the Ubuntu Server ISO to the flash drive in a way that your computer can boot from it. Do not simply copy the ISO file onto the USB drive. That is a common beginner mistake. The drive must be flashed using a proper imaging tool.
Also, back up anything important from the USB drive first. Flashing the ISO will erase the drive. If your USB contains vacation photos, tax files, or that one mysterious folder named “final-final-real-version,” move them somewhere safe before continuing.
Option A: Create the USB on Windows Using Rufus
Rufus is a popular Windows tool for creating bootable USB drives. It is lightweight, reliable, and widely used for Linux installation media.
- Insert your USB flash drive into the Windows computer.
- Open Rufus.
- Under Device, select the correct USB drive.
- Under Boot selection, choose the Ubuntu Server 21.04 ISO.
- For modern computers, choose GPT partition scheme and UEFI target system.
- For older BIOS systems, choose MBR.
- Click Start.
- If Rufus asks whether to write in ISO mode or DD mode, try ISO mode first unless you have a specific reason to use DD mode.
- Wait until the process finishes, then safely eject the USB drive.
If the USB does not boot later, recreate it using DD mode or try another USB port. Some older machines are pickier than a cat choosing a cardboard box.
Option B: Create the USB on macOS Using balenaEtcher
On macOS, balenaEtcher is one of the easiest ways to flash Ubuntu Server to a USB drive. It has a simple three-step workflow: select image, select target, flash.
- Insert the USB drive into your Mac.
- Open balenaEtcher.
- Select the Ubuntu Server 21.04 ISO file.
- Select the USB drive as the target.
- Click Flash.
- Enter your macOS password if prompted.
- Wait for Etcher to finish writing and validating the USB.
macOS may complain that the finished USB drive is unreadable. That is normal because the drive now contains Linux installation media. Do not initialize or erase it. Just eject it like a calm professional.
Option C: Create the USB on Ubuntu Using Startup Disk Creator
If you already have an Ubuntu desktop system, you can use Startup Disk Creator. It is included with many Ubuntu installations and is designed specifically for creating Ubuntu bootable USB media.
- Insert the USB flash drive.
- Open Startup Disk Creator.
- Select the Ubuntu Server 21.04 ISO as the source image.
- Select the correct USB drive as the target.
- Click Make Startup Disk.
- Confirm that the drive can be erased.
- Wait for the process to complete.
When finished, remove the USB drive safely. You now have a bootable Ubuntu Server 21.04 installer.
Step 3: Boot the Target Machine from USB
Insert the bootable USB drive into the computer where you want to install Ubuntu Server. Turn the machine on and open the boot menu. The key depends on the manufacturer. Common boot menu keys include F12, F11, F10, Esc, or F8. For BIOS or UEFI settings, common keys include Del, F2, or Esc.
Select the USB drive from the boot menu. If you see two options, one labeled UEFI and one not, choose the UEFI option for modern systems. If the USB does not appear, try another USB port, disable Fast Boot in firmware settings, or check whether Secure Boot is interfering with the boot process.
Once the installer loads, you should see the Ubuntu Server installation interface. Ubuntu Server does not use a traditional desktop installer. It uses a clean text-based interface called Subiquity. It may look minimal, but it is powerful and efficient. Servers do not need glitter. They need stability.
Step 4: Choose Language and Keyboard Layout
The first installer screens ask for your language and keyboard layout. Choose the language you want to use during installation, then select your keyboard layout. If you are using a standard U.S. keyboard, the default English (US) layout is usually correct.
You can test the keyboard layout in the input field provided by the installer. This is worth doing if you use a non-U.S. keyboard, because typing passwords with the wrong keyboard layout is a special kind of pain. Nobody wants to discover after rebooting that their password contains a symbol that moved to another key.
Step 5: Configure Network Settings
Ubuntu Server will detect available network interfaces. If your machine is connected by Ethernet and your router provides DHCP, the installer usually configures networking automatically. You will see an IP address assigned to the interface.
If you need a static IP address, choose manual configuration. Enter the IP address, subnet, gateway, and DNS servers carefully. For example, a home lab server might use an address like 192.168.1.50, a gateway like 192.168.1.1, and DNS servers such as your router or public DNS providers.
For most beginners, DHCP is fine during installation. You can always configure a static IP later after the system is installed. The important thing is that the server has network access so it can download packages, install updates, and enable remote management.
Step 6: Configure Proxy and Ubuntu Archive Mirror
The installer may ask for an HTTP proxy. Most home users and small office users can leave this blank. Proxy settings are mainly used in corporate networks, schools, or controlled environments where internet traffic must pass through a proxy server.
Next, the installer asks for the Ubuntu archive mirror. The default mirror usually works. If you are installing in a region where another mirror is faster, you can change it, but for most installations, the default option is perfectly acceptable.
Step 7: Configure Storage
Storage is the part where you should slow down and read carefully. The installer can erase disks, create partitions, and set up Logical Volume Management. If you choose the wrong disk, the installer will not politely ask your old data whether it wants to survive. It will simply overwrite it.
Use an Entire Disk
For a fresh server installation, the easiest option is Use an entire disk. This tells Ubuntu to install itself on the selected drive. You can also choose to set up LVM, which makes future storage management more flexible. LVM is useful if you expect to resize volumes, add disks, or manage storage more professionally.
If this is a simple home server, test server, or learning machine, the guided storage option is usually fine. If this is a multi-disk server, production machine, or dual-boot setup, review every storage screen carefully before confirming.
Manual Partitioning
Manual partitioning gives you full control. You might create a small EFI system partition, a root partition mounted at /, optional separate partitions for /var or /home, and swap space if needed. Manual partitioning is excellent for advanced users, but beginners should not feel pressured to use it.
For a basic Ubuntu Server 21.04 USB installation, guided storage keeps the process clean and avoids unnecessary complexity. You can become a partitioning wizard later. Every wizard starts somewhere.
Step 8: Create Your Server Profile
Next, Ubuntu asks you to create the main user account and server profile. You will enter your name, the server name, a username, and a password.
Choose a server name that is short, memorable, and meaningful. Examples include webserver01, homelab, nasbox, or ubuntu2104. Avoid spaces and overly cute names unless you enjoy explaining to future you why the production server is called banana-fortress.
Use a strong password. Even if the server is only on your local network, good habits matter. A strong password should be long, unique, and not reused from another account.
Step 9: Install OpenSSH Server
The installer gives you the option to install OpenSSH Server. In most cases, you should enable it. SSH allows you to manage the server remotely from another computer using a terminal.
For example, after installation, you can connect from another machine using:
If your username is alex and your server IP is 192.168.1.50, the command would be:
You may also have the option to import SSH keys from services such as GitHub or Launchpad. SSH keys are more secure than passwords when configured properly, but password login is acceptable for a simple lab setup. For internet-facing servers, use SSH keys and harden the configuration after installation.
Step 10: Choose Featured Server Snaps
Ubuntu Server may offer optional server snaps during installation. These can include popular tools or services. If you are new to Ubuntu Server, it is often better to skip these during installation and add software later. A clean base system is easier to understand and troubleshoot.
After the system is installed, you can install packages using:
This gives you more control and helps you learn what is actually running on your server. Minimal installations are like tidy garages: easier to work in, easier to fix, and less likely to hide a raccoon.
Step 11: Finish Installation and Reboot
After confirming the installation summary, Ubuntu Server begins copying files and installing the system. Depending on your hardware and USB speed, this can take a few minutes. Older USB drives may move at the speed of a sleepy snail, so patience helps.
When installation is complete, choose Reboot Now. The installer will prompt you to remove the USB drive. Remove it, then press Enter. If you forget to remove the USB, the machine may boot back into the installer instead of your new system. This is not a disaster, just a tiny comedy routine performed by your BIOS.
After rebooting, you should see a login prompt. Enter the username and password you created during installation.
Step 12: Run First Update Commands
After logging in, run the basic update commands:
However, because Ubuntu Server 21.04 is end-of-life, standard repositories may not work the way they did when the release was active. You may need to use old release repositories for legacy package access. This is another reason Ubuntu 21.04 should not be used for production today.
If your goal is simply to learn Linux server administration, consider repeating the same process with a current Ubuntu LTS version. The installation flow is similar, but the system will be safer and easier to maintain.
Common Problems When Installing Ubuntu Server 21.04 via USB
The USB Drive Does Not Boot
If the USB drive does not boot, recreate it using a trusted flashing tool. Try another USB port, preferably a USB 2.0 port on older machines. Check BIOS or UEFI settings and make sure USB boot is enabled. If the machine supports both legacy BIOS and UEFI, try the other boot mode.
The Installer Cannot Find the Disk
If Ubuntu Server cannot detect the internal drive, check storage controller settings in BIOS or UEFI. Some systems use RAID or Intel RST modes that may cause Linux installers to behave differently. AHCI mode is often more Linux-friendly, but changing this setting can affect existing operating systems, so be careful.
No Network Connection During Installation
Use Ethernet if possible. Wi-Fi support in server installers can be more limited depending on the hardware. If the network is not detected, finish the installation without network access if the installer allows it, then configure drivers and networking later.
Wrong Disk Was Selected
This is why storage confirmation screens matter. If you have multiple drives, disconnect drives you do not want to touch before installing. It is a simple physical safety trick that has saved many people from accidental data loss.
Best Practices After Installing Ubuntu Server
Once Ubuntu Server is installed, there are several smart next steps. First, update the package list and installed software if repositories are available. Second, confirm your IP address using:
Third, test SSH from another computer. Fourth, create a backup plan before storing anything important. Fifth, install only the services you actually need. A server with fewer services has fewer things to maintain and fewer doors for trouble to knock on.
If you plan to expose the server to the internet, configure a firewall using UFW, disable unnecessary services, consider SSH key authentication, and keep the system updated. For Ubuntu 21.04 specifically, do not expose it publicly unless you fully understand the risk of running an unsupported operating system.
Real-World Experience: Lessons from Installing Ubuntu Server 21.04 via USB
Installing Ubuntu Server 21.04 via USB is usually simple, but real-world installations have a personality. Sometimes that personality is friendly. Sometimes it acts like a printer with opinions.
One practical lesson is that the USB drive matters more than people expect. Cheap or very old USB drives can cause strange failures: slow booting, corrupted files, installer freezes, or random read errors. If the installation fails twice with no clear reason, try a different USB drive before blaming Ubuntu, your server, the moon, or your life choices. A decent 8 GB or 16 GB USB drive from a reliable brand can save a lot of time.
Another lesson is to match the boot mode with your system. Modern machines generally prefer UEFI with GPT. Older machines may need legacy BIOS with MBR. If you create the USB in one mode and boot it in another, the installer may not behave as expected, or the installed system may not boot afterward. When in doubt, check the firmware settings and keep the installation mode consistent from USB boot to final system boot.
Network preparation also makes a big difference. Ubuntu Server is designed for server use, and servers are happiest with Ethernet. Wi-Fi can work on some hardware, but it is not the smoothest path for a beginner. If you are setting up a home lab, plug the machine into the router with a cable during installation. After the system is running, you can experiment with wireless networking if needed.
Storage is another area where experience teaches caution. If the target machine has more than one disk, label them mentally before starting. Better yet, unplug any disk that should not be touched. The Ubuntu installer clearly shows storage choices, but tired humans are remarkably talented at selecting the wrong drive at 1:00 a.m. Protect yourself from future regret by simplifying the disk layout before installation.
It is also worth writing down the username, password, server name, and IP address during setup. This sounds obvious, but many people finish an installation and immediately forget the exact username they created. The server then sits at the login prompt like a bouncer at a very exclusive club. A small note saves the day.
Finally, remember that Ubuntu Server 21.04 is an old interim release. Installing it is useful if you are recreating a historical environment, testing software from that period, studying Ubuntu’s server installer, or working with a legacy guide. But for a real server that stores important data or faces the internet, use a supported LTS release. The installation skills transfer almost perfectly, and you get modern security updates. In other words, practice on the old hippo if you want, but let a newer long-term-support penguin guard the castle.
Conclusion
Installing Ubuntu Server 21.04 via USB is a practical way to learn Linux server deployment, understand bootable installation media, and practice server setup from the ground up. The process is simple when broken into clear steps: download the ISO, flash it properly to a USB drive, boot from USB, configure language, keyboard, network, storage, user profile, SSH, and then reboot into your new server.
The biggest thing to remember is that Ubuntu Server 21.04 is no longer supported. That does not make it useless, but it changes where it belongs. Use it for labs, testing, and learning. For production, choose a currently supported Ubuntu LTS release. Your future self, your security logs, and your blood pressure will all be grateful.
Note: This article is based on real Ubuntu Server installation behavior, official Ubuntu documentation practices, bootable USB tool workflows, and known Ubuntu 21.04 lifecycle information. Ubuntu Server 21.04 is end-of-life, so use it for learning or legacy testing rather than production.