www/content/blog/commands/mdadm.md

title	date	description	tags
mdadm	2011-11-15	some mdadm command examples	linux simple utilities

Watch the array status

{{< highlight sh >}} watch -d -n10 mdadm --detail /dev/md127 {{< /highlight >}}

Recovery from livecd

{{< highlight sh >}} mdadm --examine --scan >> /etc/mdadm.conf mdadm --assemble --scan /dev/md/root mount /dev/md127 /mnt # or vgscan... {{< /highlight >}}

If auto detection does not work, you can still assemble an array manually : {{< highlight sh >}} mdadm --assemble /dev/md0 /dev/sda1 /dev/sdb1 {{< /highlight >}}

Resync an array

First rigorously check the output of cat /proc/mdstat {{< highlight sh >}} mdadm --manage --re-add /dev/md0 /dev/sdb1 {{< /highlight >}}

Destroy an array

{{< highlight sh >}} mdadm --stop /dev/md0 mdadm --zero-superblock /dev/sda mdadm --zero-superblock /dev/sdb {{< /highlight >}}