Hello,
I have two disks sda and sdb. One of the was broken so I have changed the broken disk with a working one. I started the server in rescue mode, and created the partional table, and added all the partitions to the software raid.
I have added the partitions to the RAID, and reboot.
# mdadm /dev/md0 --add /dev/sdb1
# mdadm /dev/md1 --add /dev/sdb2
# mdadm /dev/md2 --add /dev/sdb3
# mdadm /dev/md3 --add /dev/sdb4
After reboot, server did not boot. So I do the followings:
# mount /dev/md1 /mnt/rescue
# mount /dev/md0 /mnt/rescue/boot
# mount -o bind /dev /mnt/rescue/dev
# mount -o bind /proc /mnt/rescue/proc
# mount -o bind /dev/shm /mnt/rescue/dev/shm
# mount -o bind /sys /mnt/rescue/sys
# chroot /mnt/rescue
I checked the device.map
# cat /boot/grub/device.map
(hd0) /dev/sda
(hd1) /dev/sdb
And, install the grub.
# grub
Probing devices to guess BIOS drives. This may take a long time.
GNU GRUB version 0.97 (640K lower / 3072K upper memory)
[ Minimal BASH-like line editing is supported. For the first word, TAB
lists possible command completions. Anywhere else TAB lists the possible
completions of a device/filename.]
grub> root (hd0,0)
root (hd0,0)
Filesystem type is ext2fs, partition type 0xfd
grub> setup (hd0)
setup (hd0)
Checking if "/boot/grub/stage1" exists... yes
Checking if "/boot/grub/stage2" exists... yes
Checking if "/boot/grub/e2fs_stage1_5" exists... yes
Running "embed /boot/grub/e2fs_stage1_5 (hd0)"... 15 sectors are embedded.
succeeded
Running "install /boot/grub/stage1 (hd0) (hd0)1+15 p (hd0,0)/boot/grub/stage2 /boot/grub/grub.conf"... succeeded
Done.
grub> root (hd1,0)
root (hd1,0)
Filesystem type is ext2fs, partition type 0xfd
grub> setup (hd1)
setup (hd1)
Checking if "/boot/grub/stage1" exists... yes
Checking if "/boot/grub/stage2" exists... yes
Checking if "/boot/grub/e2fs_stage1_5" exists... yes
Running "embed /boot/grub/e2fs_stage1_5 (hd1)"... 15 sectors are embedded.
succeeded
Running "install /boot/grub/stage1 (hd1) (hd1)1+15 p (hd1,0)/boot/grub/stage2 /boot/grub/grub.conf"... succeeded
Done.
grub> quit
quit
But it still does not boot. What should I do at this point? What do you suggest?
Disk informations
# fdisk -l /dev/sd[ab]
Disk /dev/sda: 1500.3 GB, 1500301910016 bytes
255 heads, 63 sectors/track, 182401 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00090dd1
Device Boot Start End Blocks Id System
/dev/sda1 * 1 131 1052226 fd Linux raid autodetect
/dev/sda2 132 5353 41945715 fd Linux raid autodetect
/dev/sda3 5354 96733 734009850 fd Linux raid autodetect
/dev/sda4 96734 182401 688128210 fd Linux raid autodetect
Disk /dev/sdb: 1500.3 GB, 1500301910016 bytes
255 heads, 63 sectors/track, 182401 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0xf5c3aa6a
Device Boot Start End Blocks Id System
/dev/sdb1 * 1 131 1052226 fd Linux raid autodetect
/dev/sdb2 132 5353 41945715 fd Linux raid autodetect
/dev/sdb3 5354 96733 734009850 fd Linux raid autodetect
/dev/sdb4 96734 182401 688128210 fd Linux raid autodetect
Raid info
# cat /proc/mdstat
Personalities : [raid1]
md3 : active raid1 sda4[0] sdb4[2]
688128128 blocks [2/1] [U_]
resync=DELAYED
md2 : active raid1 sda3[0] sdb3[2]
734009728 blocks [2/1] [U_]
[>....................] recovery = 1.8% (13651648/734009728) finish=133.5min speed=89915K/sec
md1 : active raid1 sdb2[2] sda2[0]
41945600 blocks [2/1] [U_]
resync=DELAYED
md0 : active raid1 sda1[0] sdb1[1]
1052160 blocks [2/2] [UU]
unused devices: <none>
Mount informations
/dev/md0 is mounted /boot
/dev/md1 is mounted /
/dev/md2 and /dev/md3 is for backup and some personal data
Here is the grub.conf
# cat /mnt/rescue/boot/grub/grub.conf
timeout 5
default 0
fallback 1
title CentOS (2.6.18-238.19.1.el5)
root (hd1,0)
kernel /vmlinuz-2.6.18-238.19.1.el5 ro root=/dev/md1 vga=0x317
initrd /initrd-2.6.18-238.19.1.el5.img
title CentOS (2.6.18-238.9.1.el5)
root (hd0,0)
kernel /vmlinuz-2.6.18-238.9.1.el5 ro root=/dev/md1 vga=0x317
initrd /initrd-2.6.18-238.9.1.el5.img
title CentOS (2.6.18-194.26.1.el5)
root (hd0,0)
kernel /vmlinuz-2.6.18-194.26.1.el5 ro root=/dev/md1 vga=0x317
initrd /initrd-2.6.18-194.26.1.el5.img
title CentOS (2.6.18-194.3.1.el5)
root (hd0,0)
kernel /vmlinuz-2.6.18-194.3.1.el5 ro root=/dev/md1 vga=0x317
initrd /initrd-2.6.18-194.3.1.el5.img
title CentOS (2.6.18-164.15.1.el5)
root (hd0,0)
kernel /vmlinuz-2.6.18-164.15.1.el5 ro root=/dev/md1 vga=0x317
initrd /initrd-2.6.18-164.15.1.el5.img
title CentOS Linux (2.6.18-164.11.1.el5)
root (hd0,0)
kernel /boot/vmlinuz-2.6.18-164.11.1.el5 ro root=/dev/md1 vga=0x317
initrd /boot/initrd-2.6.18-164.11.1.el5.img