I had already gotten rid of rghb. The grub2 entry on the key for booting the LiveCD reads: menuentry "CentOS 6.4 Live" { set root=(hd0,1) linux /CentOS-Live/isolinux/vmlinuz0 root=UUID=A352-6D7C ro liveimg nodiskmount nolvmmount selinux=disabled live_dir=/CentOS_Live/LiveOS initrd /CentOS-Live/isolinux/initrd0.img } The contents of the LiveCD appear in /CentOS_Live as one would expect. The boot fails right after a device scan (obvious by tens of lines listing "ataN:", "scsiN:", "sd 0:0:0:0:", etc.) with the "No root device" error below. In the rdshell, /dev/sda shows up as the internal system hard drive rather than the USB key. The USB key does not show up as /dev/sdb nor any other device that I can find. Finally, I looked in /dev/mapper (duh); it contains /dev/mapper/control, but no /dev/mapper/live-rw. Sorry for any confusion, -G. m.roth wrote: > Glenn Eychaner wrote: > > I have been following these instructions: > > https://www.centos.org/forums/viewtopic.php?t=501 > > to put a bunch of utilities (Clonezilla, SystemRescue, CentOS > > netinstall/rescue, etc.) on a single USB key. It works great for > everything (including > > Ubuntu Live) except the CentOS 6.4 LiveCD. (You can see my postings at > the bottom of > > the forum.) When booting the LiveCD, I got: > > Kernel panic - not syncing: Attempted to kill init! > > Pid: 1, comm: init Not tainted 2.6.32-358.el6.i686 #1 > > After removing "quiet" and adding "selinux=disabled", I got more > > Get rid of rhgb, too. > > > information; the boot stalls after finding devices, and gives: > > No root device "block:/dev/mapper/live-rw" found > > dracut suggests adding "rdshell", which I did. This was not helpful (I > > had no idea what to do in the dracut shell), but did notice that in the > dracut > > > shell /dev/ did NOT seem to contain my USB drive at /dev/sdb as I would > expect. > > When you boot from a USB key, it always shows as /dev/sda. Second, rdshell > is a grub shell. > > Are you trying to boot from the USB? If so, I'd fix the grub menu on that, > if it's on /dev/sda1 of the flash drive, to use /dev/sda2 for the root= -- Glenn Eychaner (geychaner at lco.cl) Telescope Systems Programmer, Las Campanas Observatory