This perplexing to me. In my %post section, I tried both writing "GRUB_TIMEOUT=0" to /etc/default/grub and using sed to replace "set timeout=5" in grub2.cfg. I even put a call to grub2-mkconfig to re-write the config file after doing those things.
But on boot, grub.cfg file always contains timeout=5. Why / how is this happening?
I'm using appliance-creator, in case that's doing anything silly.