I was replacing my Ubuntu 18.04 with Lubuntu 20.04. I wanted to keep my /home partition same. After creating /root , swap and changing mount point for /home partition the installer gave a warning that /boot/efi partition is not created Lubuntu 20.04 needs /boot/efi partition to boot. Please create a FAT32 partition and mount it as /boot/efi and enable flag esp.

Then I created the /boot/efi partition but there was no esp flag(s). I had installed Ubuntu 18.04 alongside windows10.

What should I do now?

  • You mention /root, this is usually a directory a directory under '/' and not given it's own directory as it's usually empty or near empty on most installs. It maybe you meant "/" which is called root, but differs to "/root/" Have you tried the manual manual.lubuntu.me/stable/1/1.3/installation.html As I recall there are two flags I believe for /, one for /boot/efi (boot & bios-grub), but whilst I've done I think 5 successful installs this last week, I know I've had to adjust the flags at least once (even twice; ie. back & adjust until installer is happy)
    – guiverc
    Sep 8, 2020 at 2:43
  • Thanks for your answer. The installer is specifically asking for esp flag. going back once again and editing the partition I see there are no flag or flags named esp. My system has UEFI. I did not receive the same warning when I was installing Ubuntu 18.04 on the same system. What does the esp flag do? and should I proceed without enabling the *esp flag but creating /boot/EFI partition ? Sep 9, 2020 at 1:41
  • I haven't done another install recently (which I was hoping to do & then reply to you using more accurate language than my first comment). We have issues with groovy booting so I've nothing to boot for QA-testing currently. All I can currently give is as per prior comment. On the rare occasion when I don't get it right (using what I did in first comment), it won't boot as you fear, but I just repeat it & use a different combination. Given an install takes I think 10 minutes (on uEFI boxes I've never bothered remembering the exact requirements, as I just use another box during the QA install.
    – guiverc
    Sep 16, 2020 at 12:22
  • Yes if the settings aren't right, you won't be able to boot (in my experience), but I don't have windows 10 installed on boxes I use in QA testing. I would expect the re-install to correct issues just as it does with dual OS booting in my QA (where the 2nd or 3rd OS is a different GNU/Linux or other release of Ubuntu). If you want more, I'll provide lubuntu.me/links (the discourse site is probably where I'd go, but it's not the only option)
    – guiverc
    Sep 16, 2020 at 12:26

1 Answer 1


The Lubuntu manual page can be found at https://manual.lubuntu.me/stable/1/1.3/installation.html

I won't repeat what's listed there, and I'm writing this as I complete a QA-test install of groovy using today's daily.

I've performed two QA-test installs on this box in the last hour which resulted in the following partitions ; details viewed in KDE Partition Manager

  • /dev/sda1 fat32 300mb ESP (uEFI System Partition)
  • /dev/sda2 ext4 74gb ext4 (initial full disk install)
  • /dev/sda3 ext4 45gb ext4 (install alongside testcase)

I'm going to erase that anyway.

Start calamares (the installer used by Lubuntu) Opt for Manual Partitioning.. and create new partition table (GPT)

Creating partitions looks like enter image description here

sda1: ESP

  • I create a 512MB EFI system partition (larger than default; I've had issues on some boxes with smaller so I've increased size since)
  • Select mount point as /boot/efi
  • click both BIOS-GRUB & BOOT options in the flag section.

sda2: /

  • I create a ext4 partition with rest of disk space (where I'll install to).
  • Select mount point as /
  • I click both options available BIOS-GRUB & BOOT in the flag section too

I don't believe I need to select both options for both, but both those options I find easier to remember & work, so I just do that.

Click next, following prompts (giving my username, hostname etc) and reboot when it tells me to. Eject my thumb-drive when told to, and reboot into my freshly installed Lubuntu groovy system.

I login, test the system & update my QA-test entry report on iso.qa.ubuntu.com. I'm using groovy as it's useful for a QA-test (a little early for me to be thinking about 20.04.2) but it'll be identical to a focal install.

  • Note I only used that install as example. Lubuntu is also tested with XFS, BRTFS and many other variations in our testcases, and my boxes often end up with many installed systems thus why maybe I've opted to increase the EFI partition to 512MB (2^9 is just me), where I know 300MB works fine most of the time.
    – guiverc
    Sep 23, 2020 at 0:32

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .