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Grub: Ubuntu and Centos

Posted: 2009/10/10 10:24:54
by mearturo
Dear all,

I apologize for this basic question.

I had a Centos 5.3 working but I needed a lighter Linux OS for some activities, so I installed Ubuntu 9.4, and now I can't boot Centos, but I can boot XP.

It seems to be a problem in the Kernel line.

Any help will be extremely appreciated.

This is my Ubuntu menu.lst:

# menu.lst - See: grub(8), info grub, update-grub(8)
# grub-install(8), grub-floppy(8),
# grub-md5-crypt, /usr/share/doc/grub
# and /usr/share/doc/grub-doc/.

## default num
# Set the default entry to the entry number NUM. Numbering starts from 0, and
# the entry number 0 is the default if the command is not used.
#
# You can specify 'saved' instead of a number. In this case, the default entry
# is the entry saved with the command 'savedefault'.
# WARNING: If you are using dmraid do not use 'savedefault' or your
# array will desync and will not let you boot your system.
default 0

## timeout sec
# Set a timeout, in SEC seconds, before automatically booting the default entry
# (normally the first entry defined).
timeout 10

## hiddenmenu
# Hides the menu by default (press ESC to see the menu)
#hiddenmenu

# Pretty colours
#color cyan/blue white/blue

## password ['--md5'] passwd
# If used in the first section of a menu file, disable all interactive editing
# control (menu entry editor and command-line) and entries protected by the
# command 'lock'
# e.g. password topsecret
# password --md5 $1$gLhU0/$aW78kHK1QfV3P2b2znUoe/
# password topsecret

#
# examples
#
# title Windows 95/98/NT/2000
# root (hd0,0)
# makeactive
# chainloader +1
#
# title Linux
# root (hd0,1)
# kernel /vmlinuz root=/dev/hda2 ro
#

#
# Put static boot stanzas before and/or after AUTOMAGIC KERNEL LIST

### BEGIN AUTOMAGIC KERNELS LIST
## lines between the AUTOMAGIC KERNELS LIST markers will be modified
## by the debian update-grub script except for the default options below

## DO NOT UNCOMMENT THEM, Just edit them to your needs

## ## Start Default Options ##
## default kernel options
## default kernel options for automagic boot options
## If you want special options for specific kernels use kopt_x_y_z
## where x.y.z is kernel version. Minor versions can be omitted.
## e.g. kopt=root=/dev/hda1 ro
## kopt_2_6_8=root=/dev/hdc1 ro
## kopt_2_6_8_2_686=root=/dev/hdc2 ro
# kopt=root=UUID=73c45dff-e869-4cc8-a7cf-56822b50f057 ro

## default grub root device
## e.g. groot=(hd0,0)
# groot=73c45dff-e869-4cc8-a7cf-56822b50f057

## should update-grub create alternative automagic boot options
## e.g. alternative=true
## alternative=false
# alternative=true

## should update-grub lock alternative automagic boot options
## e.g. lockalternative=true
## lockalternative=false
# lockalternative=false

## additional options to use with the default boot option, but not with the
## alternatives
## e.g. defoptions=vga=791 resume=/dev/hda5
# defoptions=quiet splash

## should update-grub lock old automagic boot options
## e.g. lockold=false
## lockold=true
# lockold=false

## Xen hypervisor options to use with the default Xen boot option
# xenhopt=

## Xen Linux kernel options to use with the default Xen boot option
# xenkopt=console=tty0

## altoption boot targets option
## multiple altoptions lines are allowed
## e.g. altoptions=(extra menu suffix) extra boot options
## altoptions=(recovery) single
# altoptions=(recovery mode) single

## controls how many kernels should be put into the menu.lst
## only counts the first occurence of a kernel, not the
## alternative kernel options
## e.g. howmany=all
## howmany=7
# howmany=all

## specify if running in Xen domU or have grub detect automatically
## update-grub will ignore non-xen kernels when running in domU and vice versa
## e.g. indomU=detect
## indomU=true
## indomU=false
# indomU=detect

## should update-grub create memtest86 boot option
## e.g. memtest86=true
## memtest86=false
# memtest86=true

## should update-grub adjust the value of the default booted system
## can be true or false
# updatedefaultentry=false

## should update-grub add savedefault to the default options
## can be true or false
# savedefault=false

## ## End Default Options ##

title Ubuntu 9.04, kernel 2.6.28-15-generic
uuid 73c45dff-e869-4cc8-a7cf-56822b50f057
kernel /boot/vmlinuz-2.6.28-15-generic root=UUID=73c45dff-e869-4cc8-a7cf-56822b50f057 ro quiet splash
initrd /boot/initrd.img-2.6.28-15-generic
quiet

title Ubuntu 9.04, kernel 2.6.28-15-generic (recovery mode)
uuid 73c45dff-e869-4cc8-a7cf-56822b50f057
kernel /boot/vmlinuz-2.6.28-15-generic root=UUID=73c45dff-e869-4cc8-a7cf-56822b50f057 ro single
initrd /boot/initrd.img-2.6.28-15-generic

title Ubuntu 9.04, kernel 2.6.28-11-generic
uuid 73c45dff-e869-4cc8-a7cf-56822b50f057
kernel /boot/vmlinuz-2.6.28-11-generic root=UUID=73c45dff-e869-4cc8-a7cf-56822b50f057 ro quiet splash
initrd /boot/initrd.img-2.6.28-11-generic
quiet

title Ubuntu 9.04, kernel 2.6.28-11-generic (recovery mode)
uuid 73c45dff-e869-4cc8-a7cf-56822b50f057
kernel /boot/vmlinuz-2.6.28-11-generic root=UUID=73c45dff-e869-4cc8-a7cf-56822b50f057 ro single
initrd /boot/initrd.img-2.6.28-11-generic

title Ubuntu 9.04, memtest86+
uuid 73c45dff-e869-4cc8-a7cf-56822b50f057
kernel /boot/memtest86+.bin
quiet

### END DEBIAN AUTOMAGIC KERNELS LIST

# This is a divider, added to separate the menu items below from the Debian
# ones.
title Other operating systems:
root


# This entry automatically added by the Debian installer for a non-linux OS
# on /dev/sda2
title Microsoft Windows XP Professional
rootnoverify (hd0,1)
savedefault
makeactive
chainloader +1


# This entry automatically added by the Debian installer for an existing
# linux installation on /dev/sda3.
title CentOS release 5.3 (Final) (on /dev/sda3)
root (hd0,2)
kernel /boot/vmlinuz-2.6.18-128.4.1.el5xen root=/dev/sda3
savedefault
boot


# This entry automatically added by the Debian installer for an existing
# linux installation on /dev/sda3.
title CentOS release 5.3 (Final) (on /dev/sda3)
root (hd0,2)
kernel /boot/vmlinuz-2.6.18-128.el5xen root=/dev/sda3
savedefault
boot


# This entry automatically added by the Debian installer for an existing
# linux installation on /dev/sda3.
title CentOS release 5.3 (Final) (on /dev/sda3)
root (hd0,2)
kernel /boot/vmlinuz-2.6.18-164.el5xen root=/dev/sda3
savedefault
boot

Re: Grub: Ubuntu and Centos

Posted: 2009/10/11 17:22:19
by skolnick
First: what is the exact error you see when booting CentOS? second: in my experience, ubuntu is not lighter than CentOS :P

Regards.

Re: Grub: Ubuntu and Centos

Posted: 2009/10/11 21:22:55
by mearturo
Hi,

The error I get is: Grub Error 13 Invalid Or Unsupported Executable Format

My fdisk -l is:

Disk /dev/sda: 250.0 GB, 250059350016 bytes
255 heads, 63 sectors/track, 30401 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0xa42d04a3

Device Boot Start End Blocks Id System
/dev/sda1 1 25 200781 de Dell Utility
/dev/sda2 26 12774 102406342+ 7 HPFS/NTFS
/dev/sda3 * 12775 26798 112647780 83 Linux
/dev/sda4 26799 29474 21494970 f W95 Ext'd (LBA)
/dev/sda5 26799 26925 1020096 82 Linux swap / Solaris
/dev/sda6 26926 29474 20474811 83 Linux


You are correct, my Centos version is heavy because I need the full server version for development, my ubuntu version is just for basic internet navigation.

Re: Grub: Ubuntu and Centos

Posted: 2009/10/11 21:39:18
by CiaW
In case this helps, here's a copy of the 1st 2 entries in my centos grub.conf (same as menu.lst) -- there are some differences with what it appears Ubuntu created for you. And of course, it appears your (hd0,0) entries will be different than mine:

title CentOS (2.6.18-164.el5)
root (hd0,0)
kernel /vmlinuz-2.6.18-164.el5 ro root=LABEL=/ rhgb quiet
initrd /initrd-2.6.18-164.el5.img
title CentOS (2.6.18-128.7.1.el5xen)
root (hd0,0)
kernel /xen.gz-2.6.18-128.7.1.el5
module /vmlinuz-2.6.18-128.7.1.el5xen ro root=LABEL=/ rhgb quiet
module /initrd-2.6.18-128.7.1.el5xen.img

Hope that helps!

Grub: Ubuntu and Centos

Posted: 2009/10/12 00:52:46
by pschaff
[quote]
mearturo wrote:
...
You are correct, my Centos version is heavy because I need the full server version for development, my ubuntu version is just for basic internet navigation.[/quote]

Would sure be a lot simpler to just use CentOS for basic internet. Why does your "heavy" server install preclude this?

As to the GRUB issue, I usually chainload to the other GRUB in this kind of situation. Try a forum search for "chainload" ("ubuntu grub" would also turn up useful results):
https://www.centos.org/modules/newbb/viewtopic.php?topic_id=22439&forum=37&post_id=86864#forumpost86864
https://www.centos.org/modules/newbb/viewtopic.php?topic_id=22364&forum=37&post_id=86308#forumpost86308
https://www.centos.org/modules/newbb/viewtopic.php?viewmode=flat&topic_id=21900&forum=37

Re: Grub: Ubuntu and Centos

Posted: 2009/10/12 05:39:45
by skolnick
The "invalid or unsupported executable..." error you get suggests me something: did you install both linuxes the same architecture (I mean: both x86 or both x64)? maybe that's what the error means...

Regards.

Re: Grub: Ubuntu and Centos

Posted: 2009/10/13 14:45:12
by nouvo09
# This entry automatically added by the Debian installer for an existing
# linux installation on /dev/sda3.
title CentOS release 5.3 (Final) (on /dev/sda3)
root (hd0,2)
kernel /boot/vmlinuz-2.6.18-128.el5xen root=/dev/sda3
savedefault
boot


# This entry automatically added by the Debian installer for an existing
# linux installation on /dev/sda3.
title CentOS release 5.3 (Final) (on /dev/sda3)
root (hd0,2)
kernel /boot/vmlinuz-2.6.18-164.el5xen root=/dev/sda3
savedefault
boot[quote]
skolnick wrote:
The "invalid or unsupported executable..." error you get suggests me something: did you install both linuxes the same architecture (I mean: both x86 or both x64)? maybe that's what the error means...

Regards.[/quote]

Look
Your initrd are missing. You can add them by hand easily

Re: Grub: Ubuntu and Centos

Posted: 2009/10/13 15:22:34
by pschaff
[quote]
nouvo09 wrote:
...
Look
Your initrd are missing. You can add them by hand easily[/quote]

Good catch. Looks like an Ubuntu bug. I would still use chainload as otherwise one would need to manually update the Ubuntu GRUB /boot/grub/menu.lst entries after every CentOS kernel update.