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RAID-1 software CENTOS - no boot second disk

Hello,
I have installed a centos 6.3 with RAID-1 software and LVM.
To test it after the setup I removed the first hard drive and tried to boot on the second disk but nothing happens. Atfer a while it displays

Code:

Hard disk error

I used a kickstart for the install

Code:

# Kickstart file automatically generated by anaconda.



#version=RHEL6

install

cdrom

lang fr_FR.UTF-8

keyboard fr

network --device eth0 --mtu=1500 --bootproto static --ip 192.168.200.32 --netmask 255.255.255.0 --gateway 192.168.200.254 --nameserver 192.168.200.1,192.168.200.2 --hostname server1.company.com

rootpw  --iscrypted kkjkjknkjlgut

# Reboot after installation

reboot

firewall --service=ssh

authconfig --useshadow  --enablemd5  --enablecache

selinux --permissive

timezone Europe/Paris

bootloader --location=mbr --driveorder=sda,sdb --append="crashkernel=auto crashkernel=auto rhgb quiet"

# The following is the partition information you requested

# Note that any partitions you deleted are not expressed

# here so unless you clear all partitions first, this is

# not guaranteed to work

clearpart --drives=sda,sdb --initlabel --all

part raid.01 --size=200

part raid.02 --size=200

part raid.03 --grow --size=40600

part raid.04 --grow --size=40600

raid /boot --fstype=ext4 --level=1 --device=md0 raid.01 raid.02

raid pv.1000 --level=1 --device=md1 raid.03 raid.04

volgroup SystemVG --pesize=32768 pv.1000

logvol /var/log --fstype=ext4 --name=lv_log --vgname=SystemVG --size=10240

logvol / --fstype=ext4 --name=lv_root --vgname=SystemVG --size=4096

logvol swap --name=lv_swap --vgname=SystemVG --size=4096

logvol /tmp --fstype=ext4 --name=lv_tmp --vgname=SystemVG --size=1024

logvol /usr --fstype=ext4 --name=lv_usr --vgname=SystemVG --size=4096

logvol /var --fstype=ext4 --name=lv_var --vgname=SystemVG --size=10240







repo --name="CentOS"  --baseurl=file:///mnt/source/ --cost=100

repo --name="CentOS"  --baseurl=file:///mnt/source/ --cost=100

%packages

@Base

@Base

@Core

@Core

postfix

quota

strace

sysstat

vim-enhanced

yum-utils

-bluez-gnome

-bluez-libs

-bluez-utils

-cairo

-dnsmasq

-gamin

-irda-utils

-pcsc-lite

-sendmail

-wireless-tools

-ypbind

%end

I read online that I have to install grub on the second hard drive then I used those commands under grub shell.

Code:

root (hd0,0)

setup (hd0)

root (hd1,0)

setup (hd1)

And the two last one failed.

Code:

root (hd1,0)

 Filesystem type unknown, partition type 0xfd

and

Code:

setup (hd1)



Error 1        : Cannot mount selected partition

Any idea to get the second drive working if the first one fails ?

You may have prematurely removed the 2nd drive before it had synced up to the first.
Did you check it with cat /proc/mdstat ? to see if it had completed.
If not then copy the partition info across using
sfdisk -d /dev/sda | sfdisk /dev/sdb --force (this is an example for sda to sdb - use fdisk -l to show)
then do a
mdadm /dev/md0 --add /dev/sdb1
mdadm /dev/md1 --add /dev/sdb2
mdadm /dev/md2 --add /dev/sdb3

or whatever cat /proc/mdstat shows you for your md devices

It seems to be ok, doesn't it ?

cat /proc/mdstat

Code:

Personalities : [raid1] 

md0 : active raid1 sda1[0] sda2[1]

      204788 blocks super 1.0 [2/2] [UU]

      

md1 : active raid1 sda3[1] sdb1[0]

      77744060 blocks super 1.1 [2/2] [UU]

      bitmap: 1/1 pages [4KB], 65536KB chunk

No, this looks totally wrong for a sensible raid1 configuration
md0 should be active raid1 sda1[0] sdb1[1]
md1 should be active raid1 sda2[0] sdb2[1]

Hello
I did it again on a VM and this partition plan seems to be working.

Code:

clearpart --none

volgroup lv --pesize=4096 pv.009001

logvol /var/log --fstype=ext4 --name=lv_log --vgname=lv --size=10240

logvol / --fstype=ext4 --name=lv_root --vgname=lv --size=20480

logvol swap --name=lv_swap --vgname=lv --size=4096

logvol /usr --fstype=ext4 --name=lv_usr --vgname=lv --size=4096

logvol /var --fstype=ext4 --name=lv_var --vgname=lv --size=4096

raid /boot --fstype=ext4 --level=1 --device=md0 raid.008001 raid.008017

raid pv.009001 --level=1 --device=md1 raid.008002 raid.008018



part raid.008001 --asprimary --size=200

part raid.008002 --grow --size=200



part raid.008017 --asprimary --size=200

part raid.008018 --grow --size=200

cat /prod/mdstat

Code:

Personalities : [raid1]

md0 : active raid1 sdb1[1] sda1[0]

      204788 blocks super 1.0 [2/2] [UU]



md1 : active raid1 sdb2[1] sda2[0]

      83679164 blocks super 1.1 [2/2] [UU]

      bitmap: 1/1 pages [4KB], 65536KB chunk



unused devices: <none>