diff --git a/roles/ceph-osd/vars/main.yml b/roles/ceph-osd/vars/main.yml
index fcda64e2e..a47ff649e 100644
--- a/roles/ceph-osd/vars/main.yml
+++ b/roles/ceph-osd/vars/main.yml
@@ -32,6 +32,14 @@ devices:
   - /dev/sdd
   - /dev/sde
 
+# Device discovery is based on the Ansible fact 'ansible_devices'
+# which reports all the devices on a system. If chosen all the disks
+# found will be passed to ceph-disk. You should not be worried on using
+# this option since ceph-disk has a built-in check which looks for empty devices.
+# Thus devices with existing partition tables will not be used.
+# This mode prevents you from filling out the 'devices' variable above.
+#
+osd_auto_discovery: false
 
 # I. First scenario: journal and osd_data on the same device
 # Use 'true' to enable this scenario