Software RAID (MD)

see also Hardware configuration

Replace the disk, then copy the partition information from the good disk, randomize the UUID, and re-read the partition information into the system. First, install gdisk from the Debian Universe repositories.

apt-get install gdisk
sgdisk -R=/dev/sdb /dev/sda
sgdisk -G /dev/sdb
partprobe

Taken from How can I quickly copy a GPT partition scheme from one hard drive to another?

Other resources on mdadm and How do I rename an mdadm raid array?:

• https://raid.wiki.kernel.org/index.php/Recovering_a_failed_software_RAID
• http://en.wikipedia.org/wiki/Mdadm#Creating_an_array
• https://access.redhat.com/site/documentation/en-US/Red_Hat_Enterprise_Linux/4/html/Cluster_Logical_Volume_Manager/VG_activate.html
• https://raid.wiki.kernel.org/index.php/RAID_Recovery
• http://www.cyberciti.biz/faq/linux-creating-software-raid-one-arrays/
• http://www.cyberciti.biz/faq/linux-server-rename-an-mdadm-raid-array/
• SMART tests with smartctl
• Smartmontools and fixing Unreadable Disk Sectors
• What SMART Stats Tell Us About Hard Drives

Setup configuration:

mdadm -Es >> /etc/mdadm/mdadm.conf

1. Install Ubuntu Hardy (8.04) Alternate Install: F6-F6-Expert Mode
2. Install Raid1 with MD package activated and assign mount points

to check wether root and swap are mounted, enter:

mount
free -m -t

to check mismatching uuid's, enter:

ls -la /dev/disk/by-uuid
cat /etc/fstab

to fix, do:

vim /etc/fstab

replace the uuid's found in fstab with the ones found in /dev/disk. Make sure you copy the correct uuid (md0, md1) to the respective entry in fstab.