Bug#655532: grub-installer: iso9660 filesystems and GRUB
DISTRIB_RELEASE="7.0 (wheezy) - installer build 20120111-00:07"
The installation to a USB stick (device /dev/sdc) proceeded smoothly
Unable to install GRUB in /dev/sdc
Executing 'grub-install /dev/sdc' failed
This is a fatal error
The syslog expands on this (but truncates the error message):
Jan 11 19:37:49 grub-installer: info: Installing grub on '/dev/sdc'
Jan 11 19:37:49 grub-installer: info: grub-install supports --no-floppy
Jan 11 19:37:49 grub-installer: info: Running chroot /target grub-install --no-floppy --force "/dev/sdc"
Jan 11 19:37:51 grub-installer: /usr/sbin/grub-setup: error:
Jan 11 19:37:51 grub-installer:
Jan 11 19:37:51 grub-installer: hd2 appears to contain a iso9660
filesystem which isn't known to reserve space for
DOS-style boot. Installing GRUB there could result
in FILESYSTEM DESTRUCTION if valuable data is
overwritten by grub-setup (--skip-fs-p
Some background to GRUB's behaviour is in the thread starting at
The USB stick had held an isohybrid image, so information that there is
an iso9660 filesysten on it is in its first 64 sectors and this is not
touched by partitioning. It would be nice if this situation could be
recognized by grub-installer and for the installation to be capable of
continuing at the user's own risk after a suitable warning message had