[Bug 1812752] Re: UX: changing GRUB_CMDLINE_LINUX_DEFAULT in /etc/default/grub has no effect in cloud images

[Robie Basak]

I was going to say that you could use debconf to provide a setting that
allows the user to change this, and then have cloud images do that
instead of using the .d/ directory.

Then I looked and found some code to do that already, in grub-efi-
amd64.config, using the grub2/linux_cmdline_default debconf key.

I'm not sure how that relates to cloud images in general, but that's a
clear path forward I think?

>  i don't think there's much that can be done on the cloud image side
as all that's done is add the cloudimg-settings file

Well, the point is, don't do that, since that's what creates the problem
:-)

** Changed in: cloud-images
       Status: Invalid => New

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to grub2 in Ubuntu.
https://bugs.launchpad.net/bugs/1812752

Title:
  UX: changing GRUB_CMDLINE_LINUX_DEFAULT in /etc/default/grub has no
  effect in cloud images

Status in cloud-images:
  New
Status in grub2 package in Ubuntu:
  Confirmed

Bug description:
  I need to modify the kernel command line, such as to work around bug
  1573095. I edit GRUB_CMDLINE_LINUX_DEFAULT in /etc/default/grub and
  rerun update-grub but this has no effect.

  The reason is that this is redefined in
  /etc/default/grub.d/50-cloudimg-settings.cfg and that one overrides
  /etc/default/grub. I was misled by the comment in /etc/default/grub
  and information widely available on the Internet that editing
  /etc/default/grub is sufficient, and looked no further.

  I understand the reason for not modifying /etc/default/grub in cloud
  image builds (to avoid future conffile prompts) and I'm not suggesting
  that it should be modified. To fix this UX issue properly I think the
  grub package needs to provide a mechanism that allows cloud image
  builds to override the default without dropping in an overriding file
  (or for that override file to be the sole place that users need to
  look).

  This affects grub2 2.02-2ubuntu8.9 from Bionic cloud image build
  20190114 for example.

To manage notifications about this bug go to:
https://bugs.launchpad.net/cloud-images/+bug/1812752/+subscriptions