We found three causes of the "headless server waits forever for someone to press a key" problem with grub2:
1) "apt-get updgrade" can trigger "grub-setup". If by chance there happens to be a USB drive attached with Linux on it... grub will find it. And suddenly you have two OS's and grub asks.
2) If a previous boot fails (for example because of a power failure in the middle), the next boot waits forever for a keypress.
3) On a kiosk, if a visitor happens to press the shift key (or it is stuck) at boot time, the machine won't finish the boot.
All three issues are problems for unattended/kiosk uses of Ubunu.
SOLVED (sort of):
We found three causes of the "headless server waits forever for someone to press a key" problem with grub2:
1) "apt-get updgrade" can trigger "grub-setup". If by chance there happens to be a USB drive attached with Linux on it... grub will find it. And suddenly you have two OS's and grub asks.
2) If a previous boot fails (for example because of a power failure in the middle), the next boot waits forever for a keypress.
3) On a kiosk, if a visitor happens to press the shift key (or it is stuck) at boot time, the machine won't finish the boot.
All three issues are problems for unattended/kiosk uses of Ubunu.