doc: Cherry picked from master to next. Adds comments on naming OSDs.

Signed-off-by: John Wilkins <john.wilkins@inktank.com>

diff --git a/doc/rados/configuration/osd-config-ref.rst b/doc/rados/configuration/osd-config-ref.rst
index 8d1ab4ac1a23f0e3dd9b7f74f2f36fc222d85978..9486b55912fa93ccc387e23d6a83e27502987054 100644 (file)
--- a/doc/rados/configuration/osd-config-ref.rst
+++ b/doc/rados/configuration/osd-config-ref.rst
@@ -5,7 +5,30 @@
 You can configure OSDs in the Ceph configuration file, but OSDs can use the
 default values and a very minimal configuration. A minimal OSD configuration
 sets ``osd journal size`` and ``osd host``,  and uses default values for
-nearly everything else. 
+nearly everything else.
+
+OSDs are numerically identified in incremental fashion, beginning with ``0``
+using the following convention. ::
+
+       osd.0
+       osd.1
+       osd.2
+
+In a configuration file, you may specify settings for all OSDs in the cluster
+by adding configuration settings to the ``[osd]`` section of your configuration
+file. To add settings directly to a specific OSD (e.g., ``osd host``), enter 
+it in an OSD-specific section of your configuration file. For example:
+
+.. code-block:: ini
+       
+       [osd]
+               osd journal size = 1024
+       
+       [osd.0]
+               osd host = osd-host-a
+               
+       [osd.1]
+               osd host = osd-host-b
 
 
 General Settings