nas brot # mdadm --manage --set-faulty /dev/md2 /dev/sdc3
mdadm: set /dev/sdc3 faulty in /dev/md2
nas brot # mdadm --manage --set-faulty /dev/md4 /dev/sdc4
mdadm: set /dev/sdc4 faulty in /dev/md4
nas brot # mdadm --manage /dev/md2 -r /dev/sdc3
mdadm: hot removed /dev/sdc3 from /dev/md2
nas brot # mdadm --manage /dev/md4 -r /dev/sdc4
mdadm: hot removed /dev/sdc4 from /dev/md4