This
https://wiki.gentoo.org/wiki/GRUB2/Configuration_variables
has
GRUB_DISABLE_LINUX_UUID false If true, ${GRUB_DEVICE} is passed in the root
parameter on the kernel command line.
If false, ${GRUB_DEVICE_UUID} is passed in the root parameter on the kernel
command line when an initramfs is available.
So it looks like i can't set root= to a UUID unless i use an initramfs -
can anyone confirm?
In /usr/src/linux/admin-guide/kernel-parameters.txt it has;
root= [KNL] Root filesystem
See name_to_dev_t comment in init/do_mounts.c.
And in do_mounts.c it mentions PARTUUID= and PARTLABEL= but i dont know C
so don't know what to make of it.
Background is that after adding a new disk the system doesn't boot, so i'm
assuming that the /dev/sdX device names are now pointing to different
hardware, so i want to fix that by using persistent names.
