If your disk has RAID metadata that it is impossible to erase with common ways but you'd like to erase it to use the disk with no RAID, then, Attach the disk to another mashine that Linux is installed and boot it first, Next, Erase RAID metadata with the following way.  Install mdadm to verify disks. [root@dlp ~]# yum -y install mdadm dmraid  If your disk has RAID metadata, following result is shown. The example below, it shows there is RAID metadata at 124914352 sector on /dev/sdb. [root@dlp ~]# dmraid -r /dev/sdb: ddf1, ".ddf1_disks", GROUP, ok, 124914352 sectors, data@ 0  Erase RAID metadata with mdadm like follows. [root@dlp ~]# mdadm --zero-superblock /dev/sdb [root@dlp ~]# dmraid -r no raid disks and with names: "/dev/sdb"  If it's impossible to erase with the way of , overwrite with dd command like follows. [root@dlp ~]# dd if=/dev/zero of=/dev/sdb bs=512 seek=124914352 [root@dlp ~]# dmraid -r no raid disks and with names: "/dev/sdb" =================================================== Removing RAID metadata Sometimes a hardware RAID controller or fakeraid (BIOS) can leave metadata that makes it impossible to install Windows or Linux, or it installs correctly, but causes a kernel panic or a 0xb7 blue screen error on the first boot. The only method I could find to delete the metadata *quickly* is to zero out the last 512KB of data on the disk using the following command: dd if=/dev/zero of=$YOUR_DEV bs=512 seek=$(( $(blockdev --getsz $YOUR_DEV) - 1024 )) count=1024 Replace $YOUR_DEV with the physical device, such as /dev/sda You could just zero the whole disk, but that could take hours. This command executes in less than a second.
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