Sometimes when you put a harddisk, that belonged to a hardware RAID set, in a new server and you are trying to install Linux or Windows, it complains that the RAID metadata is still present and must be removed.
We can resolve this error easily by executing following command in rescue mode:
# dd if=/dev/zero of=/dev/sda bs=512 seek=$(( $(blockdev --getsz /dev/sda) - 1024 )) count=1024
** Make sure to replace '/dev/sda' with the correct harddisk.
This command only takes a matter of seconds and the installation of the operating system should go fine after that.
You can also zero out the entire disk, but that can take hours. Why waste hours when you can have it fixed in seconds?