Comment 4 for bug 1550604

Reviewed: https://review.openstack.org/286283
Committed: https://git.openstack.org/cgit/openstack/ironic-lib/commit/?id=042aa9ab5a27e251c8fb2f1855695cf5e791ecf5
Submitter: Jenkins
Branch: master

commit 042aa9ab5a27e251c8fb2f1855695cf5e791ecf5
Author: Gonéri Le Bouder <email address hidden>
Date: Fri Feb 26 11:27:54 2016 -0500

    use wipefs to erase FS meta information

    destroy_disk_metadata should destroy a bit more data than expected if we
    want to be sure grub won't conflict with remaining bits of filesystem.
    grub probes the hard drive to find remaining partition or filesystem. If
    it find something, it will refuse to install itself on the disk.

    By using wipefs instead of dd, we not only erase the MBR and partition
    table but also all trace of filesystem, raid or partition-table signatures
    (magic strings). This without extra Python code.

    wipefs is part of util-linux which is available on all the Linux
    distribution.

    References:
    https://review.openstack.org/#/c/284347/
    https://bugzilla.redhat.com/show_bug.cgi?id=1310883
    Partial-Bug: 1550604

    Change-Id: I39637e22c344703ad48fc271f6f866aa018bbdd1