USB memory stick for Ubuntu install

[Ralf Mardorf]

On Thu, 5 Aug 2021 22:21:02 -0700, Bob wrote:
>I just had a memory problem on my desktop computer.  I have a DVD with
>the Ubuntu install on it.  What I want to do is add the BADRAM
>parameter to grub, I dont see a way to do it on a DVD.  So a USB
>memory stick should allow me to do that.
>
>My question is after I load the Ubuntu install on the USB memory stick
>can I edit /etc/default/grub and then do an update-grub to replace the
>boot grub on the USB stick?

Hi,

an USB stick with a persistent live Ubuntu comes with a few pitfalls.
I'm using a persistent live Xubuntu for backups. I don't know everything
that is possible or impossible.

One of the keywords is "casper",
https://manpages.ubuntu.com/manpages/bionic/en/man7/casper.7.html .

I'm in favour of Ventoy, https://www.ventoy.net/en/index.html . It does
use grub to chose the ISO. However, the ISO has got it's own
bootloader, too. It should be possible to add kernel parameters to the
ISO's bootloader, probably as described by
https://help.ubuntu.com/community/BootOptions#Changing_the_CD.27s_Default_Boot_Options
. Actually I don't know anything about grub parameters such as BADRAM,
you might need to use a kernel parameter, maybe memmap, see
https://unix.stackexchange.com/questions/75059/how-to-blacklist-a-correct-bad-ram-sector-according-to-memtest86-error-indicati
.

I seriously doubt that update-grub does help you. When using a
persistent live Ubuntu flavour you can install packages, configure the
install by configs in /home and /root, store data etc., but anything
boot related is tricky, perhaps impossible to do. IOW e.g. booting
another kernel or e.g. changing the actually used grub configurations
might be impossible to do.

Regards,
Ralf