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 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. (One reason it seemeed not helpful) So: 1) I used VFAT rather than ext2/3/4. Do I have to use ext2/3/4? 2) Do I need to rebuild the initramfs file somewhere in the CentOS LiveCD directory? 3) Is this just a straight-up hardware incompatibility? The computer is a brand-new SuperMicro X10SAE Haswell system.
Thanks, -G. -- Glenn Eychaner (geychaner@lco.cl) Telescope Systems Programmer, Las Campanas Observatory
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=
mark
m.roth@5-cent.us wrote:
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=
I don't think this is good advice. It is much better to use the UUID, "root=UUID=..." where the UUID can be found by blkid . In my experience, /dev/sda can become /dev/sdb under CentOS when a USB stick is inserted.
Timothy Murphy wrote:
m.roth@5-cent.us wrote:
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=
I don't think this is good advice. It is much better to use the UUID, "root=UUID=..." where the UUID can be found by blkid . In my experience, /dev/sda can become /dev/sdb under CentOS when a USB stick is inserted.
How very odd. I don't think I've *ever* seen that behavior, when a system is running on /dev/sda<whatever> as root. Now, *booting* from a USB drive, that's what I see 100% of the time, which was why I suggested editing it on the flash drive....
mark
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@lco.cl) Telescope Systems Programmer, Las Campanas Observatory
On Nov 19, 2013, at 1:55 PM, Glenn Eychaner geychaner@mac.com wrote:
I had already gotten rid of rghb. The grub2 entry on the key for booting the LiveCD reads: [...] linux /CentOS-Live/isolinux/vmlinuz0 root=UUID=A352-6D7C ro liveimg nodiskmount nolvmmount selinux=disabled live_dir=/CentOS_Live/LiveOS
D'Oh! It was obvious right after I sent the message; underscore instead of dash in live_dir. Sigh. HOWEVER, even after correcting that, it STILL doesn't boot; same exact message as before. I have a suspicion that it's not finding the USB key during the device scan, given that I can't find the USB key in /dev in rdshell.
Possibly a hardware incompatibility? (I haven't been able to test a LiveCD in the optical drive yet, but will do so now.)
-G. -- Glenn Eychaner (geychaner@lco.cl) Telescope Systems Programmer, Las Campanas Observatory
On Nov 19, 2013, at 2:07 PM, Glenn Eychaner geychaner@mac.com wrote:
Possibly a hardware incompatibility? (I haven't been able to test a LiveCD in the optical drive yet, but will do so now.)
The system boots a liveCD from the DVD drive just fine. It boots CentOS 6.4 from the hard disk. It boots everything BUT CentOS 6.4 LiveCD from the USB key.
-G. -- Glenn Eychaner (geychaner@lco.cl) Telescope Systems Programmer, Las Campanas Observatory
Glenn Eychaner wrote:
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.
That's odd, that the internal shows up as sda. However, the obvious two things: first, and esp. if the systems sees the internal as a, is that this won't work. at all - the grub entry is completely wrong - assuming that's a grub.conf. If so, you want title CenOS 6.4 Live root (hdx,0) kernel /CentOS-Live/isolinux/vmlinuz0 root=<huh0> <huh1> NO_LVM selinux=disabled <huh2> initrd /CentOS-Live/isolinux/initrd0.img
Notes: huh0: are you sure that's the actual UUID of the flash drive? You might check /dev/disk/by-id huh1: Not familiar with nodiskmount huh2: Dunno bout the live_dir... does a quick google...OH! Of course it won't work - you're using grub2, which CentOS doesn't support yet (and I hope NEVER, EVER WILL).
mark
-
Glenn Eychaner -
m.roth＠5-cent.us -
Timothy Murphy