I need to install Ubuntu 19 on a quite recent machine. I enabled all compatibility and legacy modes in BIOS to avoid UEFI.

I do not want to use UEFI.

The installation media (Ubuntu - ISO put on a USB-stick using dd) wants to force UEFI boot mode. I want simple mbr and grub boot (although Lilo was so much better than grub). I totally decline to use UEFI.

How can I install Ubuntu without UEFI?

  • 4
    New UEFI systems have two boot modes for Ubuntu live installer. But if UEFI Secure boot is on, then only UEFI is offered. Also you may need to turn on allow USB boot or full USB access or similar setting. How you boot install media, is then how it installs. You can confirm boot mode by comparing to these screens: Shows installer with screen shots. Both BIOS purple accessibility screen & UEFI black grub menu screen help.ubuntu.com/community/UEFI Even if you want the now very old BIOS boot, some advantages to gpt partitioning. But then you need a bios_grub partition.
    – oldfred
    Jul 5 '19 at 20:51
  • yes, UEFI is necessary to boot from gpt. Thanks for the important remark! NO, ist is not if you have a separated boot disk with stupid old msdos partitioning. So using gpt on your large storage media is not an issue (I do this combination successfull). Nov 19 '20 at 19:50
  • I used gpt with my old BIOS only system starting in 2010, so gpt works with BIOS systems. GPT Advantages (older 2010 but still valid) see post#2 by srs5694: ubuntuforums.org/showthread.php?t=1457901 & wiki.archlinux.org/index.php/…
    – oldfred
    Nov 19 '20 at 21:21

Force non- UEFI installation

a completely different way to avoid UEFI when installing Ubuntu

works for Ubuntu 18.04 (subsequent upgrade to 20.04 without issues):

Install via MinimalCD !


Quote from the Ubuntu Official Documentation:

The minimal iso image isn't useful for installing on UEFI-based systems that you want to run in UEFI mode. The mini iso lacks the proper files for booting the computer in UEFI mode. Thus, the computer will boot in BIOS compatibility mode, and the installation will be in BIOS mode.

  • the installation will be in BIOS mode

  • this has proven to work.

  • you can choose your Display (XFCE4, Unity, Gnome, ...) during

  • choosing server flavour during installation is provided by tasksel

  • no UEFI :-) Ubuntu without UEFI


Yet another answer ...

one more way to

avoid UEFI in a fresh & recent installation w/o upgrading:

Goal: Have a fresh install of the latest Version (currently U21 and counting) on your hard disk without UEFI.

First install some old Ubuntu 12 or 14.04 version in some free space. This is definitely free of UEFI.

Make sure you can boot this stone-age version! If necessary create a boot record on USB memory stick (!) to be absolutely sure. This can be done easy:

sudo update-grub && sudo grub-install -v /dev/sdk    (adapt USB-media name!!)

Test it. Make sure you can boot the stone-age version!

Then install the recent version like U21 Hirsute Hippo without(!) a boot option.

This option can be chosen in the installer GUI where the device for the boot record is chosen.

Boot U12 (or 14) and run update-grub, install grub. Just like

sudo update-grub && sudo grub-install -v /dev/nvme0n1    (adapt disk name!!)

Now you can boot the new Ubuntu version without UEFI :-)

In the recent version do install grub, then run update-grub, install grub like before.

Later you may delete the temp U12 partition. Use gparted (safe and capable). If its in on extended partition you need to boot from external memory stick or DVD because of the mount and swapoff issues.

You are right if you think this is a kind of change root for dummies process. Very pimitive, not much risk, proven to work.

If you like it please consider to upvote the entry :-) Thanks!


There is a simple way to install Ubuntu w/o EFI:

(caveat: this way does not always work)

After you dd the ISO file on the USB memory stick there are 2 partitions on your USB mem stick. One of them is EFI / UEFI.

Insert the stick in your operational Linux machine and invoke fdisk (sudo required).

Lets assume your stick is /dev/sdf. You see sdf1 linux and sdf2 EFI on the stick.

Use fdisk to delete partiton 2 on /dev/sdf. "Write" and end fdisk. Remove USB-stick.

Now use the stick for your installation machine.

The nuisance is gone! No more questions for a missing UEFI partition on the target disk. Smooth and simple installation.

No more additional problems and complications by UEFI!!


Yet another answer ...

Force non- UEFI installation

In the good old times ;-) there was no UEFI when you did an Ubuntu 14.04 installation. We still can leverage this.

Install your Ubuntu from an old 14.04 installation media (the usual USB-media thing does the job; download the old iso file; then just something like sudo dd of=/dev/sdj if=/mnt/datayard/iso/xubuntu-16.04.6-desktop-amd64.iso bs=1M )

Then upGRADE to recent version.

Do NOT install or optimize any stuff. No new user creation (only you have the elevated rights as lone user independent from manually assigned sudo rights).

Do upgrade iteration by iteration.

Do plenty of reboots! Some files need to be written after "first-boot".

Upgrade via GUI or just invoking


until you reach the target release level.

With do-release-upgrade -d you can even enter the latest beta ;-)

Why all the fuss??

Normally the upgrade from very old versions is not possible. Accidentially I found out it IS possible, as long as there is a vanilla installation.

Brute force:

You CAN force the upGRade by updating the Ubuntu version name in the entire /etc/apt/sources.list This is NOT smooth and does cause a lot of issues on the way. However, this can force non-vanilla installations to do the upGRADE process when it is not supported by the developers... ;-) It is the only way I am aware of to circumvent the "too old to upgrade" restrictions. I warned you!

Under the hood there are differences between updated and initial versions. I never found any disadvantages in taking the update / upgrade path.

Published this article now because this works for me on different machines. So I asume this info might be helpful for some old people out there having a no-UEFI preference.

If you liked the tips please consider to upvote the answer. Thanks!

  • If you boot your computer in BIOS mode (alias CSM alias legacy mode) into a USB drive with the Ubuntu family (Kubuntu, Lubuntu ... Xubuntu) system cloned from the iso file, then the installer will install Ubuntu in BIOS mode too (that is not in UEFI mode). You need not start from an old Ubuntu iso file and upgrade to newer versions for this to happen. dd used as you describe is a cloning tool. I prefer cloning tools with a final checkpoint, for example the Ubuntu Startup Disk Creator, Disks or mkusb.
    – sudodus
    Nov 19 '20 at 19:38
  • thanks @sudosus for the kind reply! Interesting, definitely. Well, no, my machines do NOT boot into legacy mode if i enable all matching options in the BIOS (necessary anyways). Tried this several times. Hence the articles. I toss away the GUI tools for creating boot media. Just to be safe it works. Took me many years as newbee to find dd does the job perfectly - avoiding the Windows-crap and all the spooky download "app" stuff. Malware? No thanks. Caveat: Do not bs=1M with crap memory sticks like "Philips", data will be corrupted ;-) Nov 19 '20 at 20:10
  • Please specify your computers: brand name and model. -- Some computers can be set to boot both in UEFI mode and BIOS mode with one of them as the 'preferred' mode, and it is possible to switch the preferred mode, or to set them to boot only in one of the modes. But the UEFI/BIOS systems vary a lot between computers, and you know your own computer better than I, so OK, in your case you need this double installation method in order to get what you want. -- I will upvote your 'yet another answer'.
    – sudodus
    Nov 20 '20 at 8:12

I had to enable Legacy OS boot in my BIOS (tries BIOS before UEFI?) which enabled me to install Server 20.04 LTS. I had an old Samsung RF710 from 2010 on hand.

What helped me out: https://ubuntuforums.org/showthread.php?t=2444248&s=0b4d6c9ac0681ba7acff9495e8e1bee1&p=13960694#post13960694

  • 1
    You are right: Enabling Legacy boot in BIOS is almost mandatory. Almost? Well, the issue is: Each BIOS uses a differnet name, often hidden behind marketing terms, a different functionality and some do not even offer the legacy option directly. This makes it impossible to describe what your BIOS settings should look like. The challenge is to find the way through the BIOS settings to enable legacy boot process. A lot of trial and discovery is necessary sometimes. Dec 15 '20 at 9:11

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