Hello everyone,

I am running RHEL 6.0 - 64bit
# uname -a
Linux redhat6 2.6.32-71.el6.x86_64 #1 SMP Wed Sep 1 01:33:01 EDT 2010 x86_64 x86_64 x86_64 GNU/Linux

The issue I am having with my custom boot recovery media has only recently popped its ugly head with RHEL 6.0 This was not an issue with earlier releases of RHEL 5 and earlier.

Something has changed in RHEL 6.0 that is causing my custom cd to get a kernel panic during boot up.

Here is the message during boot up:

List of all partitions:
No filesystem could mound root, tried: iso9660
Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(1,0)
Pid: 1, comm: swapper Not tainted 2.6.32-71.el6.x86_64 #1

Here are my files:




isolinux.cfg
---------------
default custom
display message
prompt 1
timeout 9000
say Press ENTER to continue booting to the Custom Recovery Menu
label custom
kernel vmlinuz
append initrd=custom.img ramdisk=92160 ramdisk_blocksize=1024 root=/dev/ram0



I believe the issue could possibly be in the way I am creating my custom.img
but I am not sure.

Please let me know what other information you require.
I am willing to pay anyone who provides an accurate solution.

Just a wild guess, but should'nt that be

Thor
(price : nothing)

I have tried other options to mounting root.

/dev/ram0 always worked in the past, which has the major minor of 1,0

# ls -l /dev/ram0
brw-rw----. 1 root disk 1, 0 Sep 22 11:37 ram0


I have tried setting root=/dev/dm-0

which in turn makes my kernel panic look like this:

List of all partitions:
No filesystem could mound root, tried: iso9660
Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0)
Pid: 1, comm: swapper Not tainted 2.6.32-71.el6.x86_64 #1

Can we have a look at the /boot/grub/grub.conf file, please?

Absolutly, here it is:

# cat /boot/grub/grub.conf
# grub.conf generated by anaconda
#
# Note that you do not have to rerun grub after making changes to this file
# NOTICE: You have a /boot partition. This means that
# all kernel and initrd paths are relative to /boot/, eg.
# root (hd0,0)
# kernel /vmlinuz-version ro root=/dev/mapper/vg_redhat6-lv_root
# initrd /initrd-[generic-]version.img
#boot=/dev/sda
default=0
timeout=5
splashimage=(hd0,0)/grub/splash.xpm.gz
hiddenmenu
title Red Hat Enterprise Linux (2.6.32-71.el6.x86_64)
root (hd0,0)
kernel /vmlinuz-2.6.32-71.el6.x86_64 ro root=/dev/mapper/vg_redhat6-lv_root rd_LVM_LV=vg_redhat6/lv_root rd_LVM_LV=vg_redhat6/lv_swap rd_NO_LUKS rd_NO_MD rd_NO_DM LANG=en_US.UTF-8 SYSFONT=latarcyrheb-sun16 KEYBOARDTYPE=pc KEYTABLE=us crashkernel=auto rhgb quiet
initrd /initramfs-2.6.32-71.el6.x86_64.img

and

I dont get it...where does the (1,0) come from?

Lemme think...

Thor

It is coming from the menu.lst file




unknown-block(1,0) is referencing /dev/ram0

Yes, I know...just, how did it get from (0.0) in the grub to (1.0) afterwards...of course, you're booting a ram-residend file system, now it hits me.

Hmm...gotta think about that one...

I understand this is not a simple task.

I will appreciate any feedback.
Please let me know if you require any other information.

This is a task worth money to me for your time or anyone's time to resolve this issue.

Hmm, okay...maybe some ground rules. We dont take money, we're volunteers....but thanks anyway.
Oh and, by the way, I for one enjoy doing this...beats crosswords any time!

Did you tinker with the boot files? It's the ones in the list:

...

Hummm, not really sure,

I did a listing of files in /boot the end .b
Nothing came up.

[RHEL6.0 - 64bit] boot # ls -l *b
total 259
-rw-r--r--. 1 root root 63 Mar 10 2011 device.map
-rw-r--r--. 1 root root 13204 Mar 10 2011 e2fs_stage1_5
-rw-r--r--. 1 root root 12516 Mar 10 2011 fat_stage1_5
-rw-r--r--. 1 root root 11748 Mar 10 2011 ffs_stage1_5
-rw-------. 1 root root 841 Mar 10 2011 grub.conf
-rw-r--r--. 1 root root 11756 Mar 10 2011 iso9660_stage1_5
-rw-r--r--. 1 root root 13220 Mar 10 2011 jfs_stage1_5
lrwxrwxrwx. 1 root root 11 Mar 10 2011 menu.lst -> ./grub.conf
-rw-r--r--. 1 root root 11940 Mar 10 2011 minix_stage1_5
-rw-r--r--. 1 root root 14300 Mar 10 2011 reiserfs_stage1_5
-rw-r--r--. 1 root root 1341 May 6 2010 splash.xpm.gz
-rw-r--r--. 1 root root 512 Mar 10 2011 stage1
-rw-r--r--. 1 root root 113044 Mar 10 2011 stage2
-rw-r--r--. 1 root root 12008 Mar 10 2011 ufs2_stage1_5
-rw-r--r--. 1 root root 11364 Mar 10 2011 vstafs_stage1_5
-rw-r--r--. 1 root root 13932 Mar 10 2011 xfs_stage1_5


Now, all these files above I copy over into the custom boot directory, but I do not modify any of these files.

Hmm, not sure if that could be a snag...installing rarthere than copying should be the approach...

Wow, this is a riddle...

Just to recap (just woke up, here) you've got a file system in memory/on disk that should be boot up. I guess your "creation" lives in there...ever tried burning a CD rom or putting it on a USB stick? That way it would be the only FS on that device. I doubt werther booting (grub-wise) of an in-memory FS like that is possible...

Never saw that B4...

Thor

I am currently using a USB stick to do this on. That is my boot recovery media.
I have also tried using a CD. Both with the same error.

okay, so, you boot off the USB stick, I gather. What's the grub menu like over there?
I assume there is a grub on de USB stick as well...