Code Block
mdadm --manage --add /dev/md0 /dev/sdb1

Remove an md device

Removing /dev/md1 as an example ...

Find which block devices the md device is built on

mdadm --detail /dev/md1

Stop the device:

mdadm --stop /dev/md1

For each block device the device is built on (here /dev/sda2):

mdadm --zero-superblock /dev/sda2

Finally remove the device:

mdadm --remove /dev/md1

Common to all RAID

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