Boot fails after recompiling custom kernel: Unable to mount root fs on unknown...

[metx1]

Boot fails after recompiling to a custom kernel (with modules kernel. replacing a precompiled static kernel) in Ubuntu server 12.10 (x64).


Current boot error message:

Kernel Panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0)
Pid: 1, comm: swapper Not tainted 3.2.12


The simple current and (unique) grub.cfg entry:


menuentry "Ubuntu 12.10, kernel 3.2.13-custom-std-ipv6-64" {
insmod part_msdos
insmod ext2
set root='hd0,msdos1'
if [ x$feature_platform_search_hint = xy ]; then
search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos1 --hint-efi=hd0,msdos1 --hint-baremetal=ahci0,msdos1 ef29aa38-32ed-41ed-aa21-7b6cd87d0f73
else
search --no-floppy --fs-uuid --set=root ef29aa38-32ed-41ed-aa21-7b6cd87d0f73
fi
linux /boot/bzImage-3.2.13-custom-std-ipv6-64 root=/dev/sda1 ro
}

The complete grub.cfg is available here: http://paste.ubuntu.com/5588079/


The current boot wide diagnose about, b., file system, id devices, and partitions
(with bootinforscript project available in sourceforge)


Boot Info Script 0.61 [1 April 2012]

============================= Boot Info Summary: ===============================

=> Grub2 (v1.99) is installed in the MBR of /dev/sda and looks at sector 1 of
the same hard drive for core.img. core.img is at this location and looks
in partition 72 for .

sda1: __________________________________________________ ________________________
File system: ext4
Boot sector type: -
Boot sector info:
Mounting failed: mount: /dev/sda1 already mounted or sda1 busy

sda2: __________________________________________________ ________________________
File system: ext4
Boot sector type: -
Boot sector info:
Operating System:
Boot files:

sda3: __________________________________________________ ________________________
File system: swap
Boot sector type: -
Boot sector info:

============================ Drive/Partition Info: =============================

Drive: sda __________________________________________________ ___________________
Disk /dev/sda: 500.1 GB, 500107862016 bytes
255 heads, 63 sectors/track, 60801 cylinders, total 976773168 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes

Partition Boot Start Sector End Sector # of Sectors Id System

/dev/sda1 * 4,096 40,962,047 40,957,952 83 Linux
/dev/sda2 40,962,048 975,718,399 934,756,352 83 Linux
/dev/sda3 975,718,400 976,764,927 1,046,528 82 Linux swap / Sola$

"blkid" output: __________________________________________________ ______________

Device UUID TYPE LABEL
/dev/sda1 * 4,096 40,962,047 40,957,952 83 Linux
/dev/sda2 40,962,048 975,718,399 934,756,352 83 Linux
/dev/sda3 975,718,400 976,764,927 1,046,528 82 Linux swap / Sola$

"blkid" output: __________________________________________________ ______________

Device UUID TYPE LABEL

/dev/sda1 ef29aa38-32ed-41ed-aa21-7b6cd87d0f73 ext4
/dev/sda2 3117e4d8-aa51-48b4-b1c1-63d452fd5d06 ext4
/dev/sda3 65c83936-878b-4968-a828-704130595036 swap

================================ Mount points: =================================

Device Mount_Point Type Options

/dev/root / ext4 (rw,relatime,errors=remount-ro,user_xattr,barrier=1,data=ordered)
/dev/sda2 /home ext4 (rw,relatime,user_xattr,barrier=1,data=ordered)

=============================== StdErr Messages: ===============================

No volume groups found
mdadm: No arrays found in config file or automatically


I can't proceed with any change in config, following other posts and how-to's are always bringing it at the same point. Anyone could help me to solve this issue?


with "head_ack_e"... ><


SOLVED following this thread: http://askubuntu.com/questions/207080/where-to-re-build-kernel-from-in-http-kernel-ubuntu-com-kernel-ppa-mainline

Adding only the installation of headers, kernel and libs .deb generated

and moving up the newest entry with the new kernel in the grub order.

Finally I got it. ;)

[metx1]

Unable to boot in grub rescue console is no manner to acces to the server.

grub rescue> set
grub rescue> root=(hd0,1)
grub rescue> prefix=(hd0,1)/boot/grub

grub rescue> linux (hd0,1)/boot/vmlinuz-3.2.12 root= /dev/sda1 ro
grub rescue> initrd (hd0,1)/boot/initrd.img-3.2.12
grub rescue> boot

(other attempts including)
insmod part_msdos
insmod ext2
insmod gzio

I'm reciviend the following message:

List of al partitions:
No filesystem could mount root, tried:
Kernel Panic - not syncing: VFS: Unable to mount root fs on unknown-block(1,0)
Pid: 1, comm: swapper Not tainted 3.2.12


This issues are happening in a dedicated server, analyzing the boot with the vKVM service.

Anyone know the reasons of it, and which would be the exact grub config. to boot properly in the re-compiled kernel? Could be also a problem of the vmlinuz image and the initrd.img ?

Thanks ;)

[nasmit]

hey,

I have the same problem right now. It is not clear how you solved it. I compiled kernel 3.6.0.rc7 and when I try to boot from it, it brings the same error message as you decribed.
I am sick of this and I am doing my project.....pls help.

..nas