mkusb

Persistent Live USB created with mkusb-dus doesn't boot in legacy BIOS mode

Bug #1889273 reported by martin
20
This bug affects 4 people
Affects Status Importance Assigned to Milestone
mkusb
New
Undecided
Unassigned

Bug Description

Hi, I created an "Persistent live" Ubuntu 20.04 USB stick using the mkusb-dus GUI. While UEFI booting works fine (if a bit slow), legacy BIOS booting isn't working (when I select the USB stick on my BIOS the screen goes black and quickly comes back to the boot device selection menu). Here are the options I selected (on an Ubuntu 20.04 box):

1. install (make a boot device)
2. 'Persistent live' - only Debian and Ubuntu
3. Selected 'sdb' (which is my USB stick)
4. upefi/usb-pack-efi (default GRUB from iso file)

I left a 50% of the remaining space for persistence.

From what I was able to examine, this creates a Protective MBR scheme with an additional Grub boot sector for legacy BIOS mode, as well as a bios_grub partition for its stage 2. This makes sense, except that legacy BIOS booting is not working for some reason.

I tried mkusb-plug, but for some reason this doesn't get rid of the Try/Install menu at the beginning like dus does, nor it uses a Protective MBR scheme. In any case, I'd rather use the tried-and-tested dus mode.

Revision history for this message
sudodus (nio-wiklund) wrote :

There can be many reasons why a computer does not boot from USB. In your case it boots in UEFI mode, but not in legacy alias BIOS mode.

I need more details in order to help you solve the problem.

- What computer is it (brand name and model)? I know that some HP computers want an MSDOS partition table to boot from grub in BIOS mode. You can select that in the settings menu of mkusb-dus.

Revision history for this message
martin (omgalvan-86) wrote :

Great response time, man! Just over a year. I ended up implementing my own solution for this, which works fine.

FWIW, the system was a Lenovo Thinkpad T570.

Revision history for this message
sudodus (nio-wiklund) wrote :

Sorry for forgetting about this channel to users.

I'm active at the Ubuntu Forums and AskUbuntu, and you can reach me via email, but I will start watching 'bugs.launchpad.net/mkusb' more regularly ...

Anyway,

- I'm glad that you implemented an own solution. Did you publish it?

- I have an old IBM Thinkpad and a newer Lenovo, V130, a consumer class laptop of the same generation as your Thinkpad, and a Lenovo Thinkstation (tower). They all work with USB drives made by mkusb. So things *should* work in your computer too.

In the Lenovo V130 I have to turn off secure boot in order to switch to booting in BIOS mode alias CSM alias legacy mode. Otherwise it will only boot in UEFI mode. I don't know, but maybe the UEFI/BIOS system is similar in your Thinkpad. If I remember correctly, there were boot problems during the development of Ubuntu 20.04, but I think that the first released version worked.

A few things have been debugged and polished in mkusb during the long delay since you reported this bug, and I think that it should work in your computer now with all current versions of Ubuntu. You are welcome to try the bleeding edge version, now via the unstable repository.

sudo add-apt-repository ppa:mkusb/unstable
sudo apt update
sudo apt install mkusb usb-pack-efi

To post a comment you must log in.
This report contains Public information  
Everyone can see this information.
Subscribing...

Other bug subscribers

Remote bug watches

Bug watches keep track of this bug in other bug trackers.