How can I boot an Ubuntu 18 live USB from GRUB?

Question

I have Ubuntu 18 and Windows 10 installed in dual boot on my machine.

I now have to do some tuning on the disk partitions and wanted to do it with the gparted available directly on the Ubuntu live USB.

The problem is that I cannot manage to get the USB booting.
I unfortunately do not have access to the BIOS. Before I installed Windows, GRUB was directly booting the USB when I typed exit on the grub> command line which is how I could install it, but now when I do exit at the GRUB command line it boots directly to Windows 10.

How can I boot to the live USB from GRUB?

I tried the solution posted in How to change boot order in grub2 to include bootable USB? and also mentioned in this blog post and it did not work.

To give more information:
it is a UEFI boot

here are the information about the USB I get using
lsblk -o name,mountpoint,label,size,uuid

NAME        MOUNTPOINT                 LABEL         SIZE UUID
sdb                                                  7.2G 
└─sdb1      /media/rayan/UBUNTU 18_0   UBUNTU 18_0   7.2G 466D-342D

score 5 · Accepted Answer · answered Dec 30 '18 at 06:09

5

Thanks to @oldfred I found a solution by using this one

I had to modify it for my case like this:

menuentry "Ubuntu 18 live" {
    search --set=root --label "UBUNTU 18_0"
    configfile /boot/grub/grub.cfg 
}

and it worked perfectly

answered Dec 30 '18 at 06:09

user3544665

61

score 3 · Answer 2 · edited Jun 12 '20 at 14:37

Booting Full Install Flash Drive from Internal Grub

What works for me is to:

Boot the computer from the internal drive.
Plug in the Full install USB drive.
Open Terminal and run:

sudo update grub
Next boot, Ubuntu from the USB drive, should appear as a grub option.

Note: Running update-grub automatically adds the new menuentry(s) to 30_os-prober. The menuentry(s) can be cut and pasted to 40_custom if desired.

How can I boot an Ubuntu 18 live USB from GRUB?

2 Answers2

Booting Full Install Flash Drive from Internal Grub