Booting Ubuntu on the hard disk from USB

[Ralf Mardorf]

On Mon, 21 Jun 2021 14:52:53 +0200, Liam Proven wrote:
>> Try by UUID  
>
>You can specify root by UUID at boot? I didn't know. Very long and
>tricky to type correctly, though.

"By default grub-mkconfig determines the UUID of the root filesystem
for the configuration. To disable this, uncomment
GRUB_DISABLE_LINUX_UUID=true." -
https://wiki.archlinux.org/title/GRUB#Additional_arguments

"Unsupported file systems

In case that GRUB does not support the root file system, an alternative
/boot partition with a supported file system must be created. In some
cases, the development version of GRUB grub-gitAUR may have native
support for the file system.

If GRUB is used with an unsupported file system it is not able to
extract the UUID of your drive so it uses classic non-persistent
/dev/sdXx names instead. In this case you might have to manually edit
/boot/grub/grub.cfg and replace root=/dev/sdXx with
root=UUID=XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX. You can use the blkid
command to get the UUID of your device, see Persistent block device
naming." -
https://wiki.archlinux.org/title/GRUB#Unsupported_file_systems

>> I'm using syslinux, not
>> grub anymore, so I need to google...  
>
>Yes, I know. Why is that?

For the better and the worse, syslinux is simpler. The configuration
for example is always straight.

Btw. my syslinux.cfg does use "root=LABEL=foo". Grub allows usage of
labels, too, "root=/dev/disk/by-label/foo".