Update documentation for recreate-disks

This also clarifies the UUIDs NEWS entry.

Signed-off-by: Iustin Pop <iustin@google.com>
Reviewed-by: Michael Hanselmann <hansmi@google.com>

NEWS

@@ -55,6 +55,8 @@ Details
   cluster destruction
 - Added automatic mode for disk replace (``gnt-instance replace-disks
   --auto``)
+- Added ``gnt-instance recreate-disks`` to re-create (empty) disks
+  after catastrophic data-loss
 - Added ``gnt-node repair-volume`` command to repair damanged LVM volume
   groups
 - Added ``gnt-instance move`` command to move instances
@@ -64,7 +66,7 @@ Details
 - Added parseable error codes to cluster verification (``gnt-cluster
   verify --error-codes``) and made output less verbose (use
   ``--verbose`` to restore previous behaviour)
-- Added UUIDs to all config entities
+- Added UUIDs to the main config entities (cluster, nodes, instances)
 - Added support for OS variants
 - Added more unittests
 - Fixed critical bug in ganeti-masterd startup

man/gnt-instance.sgml

@@ -1974,6 +1974,14 @@ node1.example.com:disk/1:/dev/drbd1
           indices, starting from zero).
         </para>
 
+        <para>
+          Note that this functionality should only be used for missing
+          disks; if any of the given disks already exists, the
+          operation will fail. While this is suboptimal,
+          recreate-disks should hopefully not be needed in normal
+          operation and as such the impact of this is low.
+        </para>
+
         <para>
           The <option>--submit</option> option is used to send the job to
           the master daemon but not wait for its completion. The job