ceph-volume: docs for the --destroy flag of lvm zap

Signed-off-by: Andrew Schoen <aschoen@redhat.com>

diff --git a/doc/ceph-volume/lvm/zap.rst b/doc/ceph-volume/lvm/zap.rst
index 8d42a9089d8940f13ae5eb34f75604316d0383f9..579cfe6e44d2b576587be44ae8c0649b2dc233d0 100644 (file)
--- a/doc/ceph-volume/lvm/zap.rst
+++ b/doc/ceph-volume/lvm/zap.rst
@@ -3,7 +3,7 @@
 ``zap``
 =======
 
-This subcommand is used to zap lvs or partitions that have been used
+This subcommand is used to zap lvs, partitions or raw devices that have been used
 by ceph OSDs so that they may be reused. If given a path to a logical
 volume it must be in the format of vg/lv. Any filesystems present
 on the given lv or partition will be removed and all data will be purged.
@@ -17,3 +17,13 @@ Zapping a logical volume::
 Zapping a partition::
 
       ceph-volume lvm zap /dev/sdc1
+
+If you are zapping a raw device or partition and would like any vgs or lvs created
+from that device removed use the ``--destroy`` flag. A common use case is to simply
+deploy OSDs using a whole raw device. If you do so and then wish to reuse that device for
+another OSD you must use the ``--destroy`` flag when zapping so that the vgs and lvs that
+ceph-volume created on the raw device will be removed.
+
+Zapping a raw device and destroying any vgs or lvs present::
+
+      ceph-volume lvm zap /dev/sdc --destroy