In the Gentoo Grub Error Collection, a possible reason for this bug is described as "can be caused by having your bios detect your disks automatically". I want to submit a new approach. I got this error to appear at boot after I had set the grub part of a new harddisk's MBR up from another disk. Some precisions..I was running a gentoo system on my old hd (master). I had copied the entire system tree over to the new and formated disk (slave). At this stage, for the remaining tasks of the copy operation, and because I planned to make my new hd a master drive, I decided to setup its MBR Grub part from my running system. I launched grub, and at the prompt I typed this : root (hd0,0) ; setup (hd1). And i think i made a big mistake here. I entered hd0,0 because i thought the futur master drive would require it. Anyway, this leads to the above mentioned error screen. I solved it by rewrinting MBR's grub bytes of that disk from the livecd. Back to existing approach, I don t think the cases are similar since I had both drives automatically detected by the bios before and after the problem was solved. Hence, in the end, maybe just add that this error can be caused by a bad setup of Grub in the MBR. Voila Reproducible: Didn't try Steps to Reproduce: 1. 2. 3. Expected Results: I think it would be a good idea to add this point to the relevant doc page. That is, the "grub grub grub grub .." error screen can also be caused by a bad setup of Grub in the MBR, and not only by a bios detection mode.
Added to the guide.
