mdadm real example of recovery and rebuilding of the array on Centos 6
In this example we have 2 drives in a RAID array and /dev/sdb is the one that failed. /dev/sda1 is also the /boot partition which we tell grub to install on /dev/sdb eg install root (hd0,0) /dev/sda1 on the new drive /dev/sdb (hd1)
First copy the partition table from /dev/sda to /dev/sdb
dd if=/dev/sda of=/dev/sdb bs=512 count=1
Run partprobe to detect the new partition table
partprobe
Add the partitions of the replacement drive /dev/sdb back to the array
mdadm --manage /dev/md0 -a /dev/sdb1
mdadm --manage /dev/md1 -a /dev/sdb2
mdadm --manage /dev/md2 -a /dev/sdb3
Install grub on the new drive
grub
root (hd0,0)
setup (hd1)
Tags:
mdadm, rebuilding, array, centos, raid, dev, sdb, sda, partition, grub, install, eg, hd, dd, bs, partprobe, detect, partitions, replacement, md,