grub-mkconfig documentation?

[Robert Heller]

Where is the documentation for grub-mkconfig?

I need to configure things properly.  The Ubuntu installer created a pretty 
dumb grub.cfg file and I need to tell grub-mkconfig how it really should 
procede when it updates /boot/grub/grub.cfg

I have two sets of kernels and two root file systems:

/boot/vmlinuz-4.15.0-* which goes with the 
/dev/mapper/sauron-ubuntu_root root file system (Ubuntu 18.04 LTS)

and

/boot/vmlinuz-2.6.32-* which goes with the /dev/mapper/sauron-c6_root root 
file system (CentOS 6.10)

What grub-mkconfig is doing is giving me the option of booting 
/dev/mapper/sauron-ubuntu_root with /boot/vmlinuz-2.6.32-* kernels, in 
addition to the proper /boot/vmlinuz-4.15.0-* with 
/dev/mapper/sauron-ubuntu_root.  It does not seem to understand that the 
2.6.32 kernels go with the /dev/mapper/sauron-c6_root root file system.

Doing 'man update-grub' directs me to man 'grub-mkconfig' which tells me to 
use info, but the info files are not actually installed.  My only experience 
is with grub 1.x and manually editing /boot/grub/grub.conf.  I know one is not 
supposed to manually edit /boot/grub/grub.cfg and somewhere under /etc/ are 
files that control how grub-mkconfig constructs /boot/grub/grub.cfg, so where 
is the documentation for that?

-- 
Robert Heller             -- 978-544-6933
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