/boot/grub2/grub.cfg has a list of menuentries with a lot of information in each. Starting at 0 count down to the one you want (you could script this out too). Then take that number and edit /etc/default/grub. In that file, add (or edit) a line: GRUB_DEFAULT=x x being the number of the menuentry you picked from looking in /boot/grub2/grub.cfg Then you have to update the grub.cfg file by running: grub2-mkconfig -o /boot/grub2/grub.

GRand Unified Boot System Essentially, Grub Legacy is easy to reconfigure by just changing a single file. Grub 2 has several config files, then once you’ve changed them, you have to run a script to update the cfg file that grub2 reads in order for the changes to take effect. Legacy config is simple: /boot/grub/menu.lst « how you change how the system boots, unique to grub legacy Grub2 config: /etc/default/grub « one of the config files