# ls /boot/grub2/grub.cfg
# ls /boot/efi/EFI/fedora/grub.cfg
# ls /boot/loader/entries/
# grub2-editenv - list
# grub2-editenv - set kernelopts="root=/dev/mapper/fedora_fc30-root ro resume=/dev/mapper/fedora_fc30-swap rd.lvm.lv=fedora_fc30/root rd.lvm.lv=fedora_fc30/swap rhgb quiet net.ifnames=0 biosdevname=0 "
# vi /etc/default/grub
# grub2-mkconfig -o /boot/grub2/grub.cfg
