On Sat, Jan 20, 2018 at 10:24 AM, Sam Varshavchik <mrsam(a)courier-mta.com> wrote:
I edited GRUB_CMDLINE_LINUX in /etc/default/grub before I installed
the most recent kernel update. However the grub entry for the new
kernel did not reflect my changes in the updated /boot/grub2/grub.cfg
Digging into this, it appears that the kernel packages run the grubby
tool which appears to be responsible for updating grub.cfg, and it
does that, apparently (not 100% sure) by cloning existing kernel
entries; and the /etc/default/grub file comes from the grub2-tool
package, and grubby doesn't know anything about it.
"/etc/default/grub" is used by "grub2-mkconfig" and not by
If I run grub2-mkconfig, it generates something completely different
from the existing grub.cfg. I have not analyzed the differences, but
using the output of grub2-mkconfig seems risky; not sure if subsequent
invocations of grubby will deal with it.
Did anyone use grub2-mkconfig before, to generate a new grub.cfg, and
then subsequently installed kernels new without grubby causing any
All distros other that Fedora and RHEL (and its clones) use
"grub2-mkconfig". I use it everywhere that I use grub2 without a
In order to get the dracut options on the kernel cmdline that the
default Fedora "etc/grub2.cfg" has, you have to add them to
"/etc/default/grub" before running "grub2-mkconfig".
"grubby" dupes the top line for the new kernel so you can use it after