Monday, 21 July 2014

Azure Configure Software RAID on Linux

Following are the steps to create RAID 5 Array on Ubuntu 12.04 LTS machine.

          è  Attach 5 hard disks each one with 500 GB.

 è Partition all hard disks.

 è Install the mdadm using the below command.
             apt-get install mdadm

 è Create the RAID 5 array using below command.
             mdadm --create /dev/md127 --level=5 --raid-devices=5 /dev/sdc1 /dev/sdd1 /dev/sde1 /dev/sdf1                     /dev/sdg1

 è Partition the RAID 5 array /dev/md127 and we get the /dev/md127p1 partition.

 è Format using the ext4 file system.
             mkfs –t ext4 /dev/md127p1

 è Add the configuration to mdadm.conf
             mdadm --detail --scan >> /etc/mdadm/mdadm.conf
             Edit the mdadm.conf file to contain only the device name and UUID like below.
             ARRAY /dev/md127 UUID=*********

 è You need to update initramfs so it contains your mdadm.conf settings during boot.
             sudo update-initramfs –u

 è Get the UUID of RAID 5 partition to add entry in fstab. Execute the below command to get UUID.
             sudo /sbin/blkid
             Copy the UUID of /dev/md127p1

 è Add the entry in fstab like below.
             UUID=****  /mountpoint      ext4       defaults, nobootwait     0              2

 è Change the bootdegraded value to true in below file.

 è Add the bootdegraded=true property in GRUB_CMDLINE_LINUX_DEFAULT like below in               /etc/default/grub file.
            GRUB_CMDLINE_LINUX_DEFAULT="console=tty1 console=ttyS0 earlyprintk=ttyS0                           rootdelay=300 bootdegraded=true"

 è After updating the above file execute the below command.
            sudo update-grub

 è Check the mount configuration using below command.
           mount -a