We have a single /dev/md0 raid1 array that is no longer needed.
Stop the array first:
# mdadm --stop /dev/md0
And then remove it:
# mdadm --remove /dev/md0
Zero the superblocks for the array disks:
# mdadm --zero-superblock /dev/xvdh # mdadm --zero-superblock /dev/xvdi
Wipe out the config file as we don’t have any other arrays on the system:
# > /etc/mdadm/mdadm.conf
Finally, remove from /etc/fstab if any records were there.