== I should learn more about Grub2

I have a long-standing dislike of Grub2 ([[eg Grub2MoveBootDisk]],
[[and Grub1VsGrub2]]). Ever since I started having to deal with it
I've felt that it's really overcomplicated, and this complexity
makes it harder to deal with. There's a lot more to know and learn
with Grub2 than there is with the original Grub, and I resent the
added complexity for what I feel should be a relatively simple
process.

You know what? The world doesn't care what I think. Grub2 is out
there and it's what (almost) everyone uses, whether or not I like
it. And [[recent events GrubDiskMismatchError]] have shown me that
I don't know enough about how it works to really troubleshoot
problems with it. As a professional sysadmin, it behooves me to fix
this sort of a gap in my knowledge for the same reason that [[I
should fix my lack of knowledge about _dpkg_ and _apt_
ShouldStudyDpkgAndApt]].

I'm probably never going to learn enough to become an expert at
Grub 2 (among other things, I don't think there's anything we do
that requires that much expertise). Right now what I think I should
learn is twofold. First, the basic operating principles, things
like where Grub 2 stores various bits of itself, how it finds things,
and how it boots. Second, a general broad view of the features and
syntax it uses for _grub.cfg_ files, to the point where I can read
through one and understand generally how it works and what it's
doing.

(I did a little bit of this [[at one point Grub2MoveBootDisk]], but
much of that knowledge has worn off.)

Unfortunately there's a third level I should also learn about. Grub2
configurations are so complex that they're actually mostly written
and updated by scripts like _grub2-mkconfig_. This means that if I
want to really control the contents of my grub.cfg on most systems,
I need to understand broadly what those scripts do and what they
get controlled by (and thus where they may go wrong). Since I don't
think this area is well documented, I expect it to be annoying and
thus probably the last bit that I tackle.

(If I cared about building custom grub2 configurations, it should
be the first area. But I don't really; I care a lot more about
understanding what Grub2 is doing when it boots our machines.)