When provisioning a Linux server (Dell rack), an administrator may install previously-used hard drives that were formally part of a RAID configuration. Such drives cannot boot into Linux until the RAID metadata partition is cleared, even if zeroing out the bits using the dd utility. To properly clear the RAID metadata, do the following:
If you get ERRORs:
[root@test-rhel7 ~]# dmraid -r -E /dev/sdc
Do you really want to erase "ddf1" ondisk metadata on /dev/sdc ? [y/n] :y
ERROR: ddf1: seeking device "/dev/sdc" to 153599999737856
ERROR: writing metadata to /dev/sdc, offset 299999999488 sectors, size 0 bytes returned 0
ERROR: erasing ondisk metadata on /dev/sdc
Try: dd if=/dev/zero of=/dev/sdc bs=512 seek=$(( $(blockdev --getsz /dev/sdc) - 1024 )) count=1024
[root@test-rhel7 ~]# dmraid -r
/dev/sdc: ddf1, ".ddf1_disks", GROUP, ok, 584843264 sectors, data@ 0
[root@test-rhel7 ~]# dd if=/dev/zero of=/dev/sdc bs=512 seek=$(( $(blockdev --getsz /dev/sdc) - 1024 )) count=1024
1024+0 records in
1024+0 records out
524288 bytes (524 kB) copied, 0.0500932 s, 10.5 MB/s
[root@test-rhel7 ~]# dmraid -r
no raid disks