doc: add documentation for undersized

Signed-off-by: Samuel Just <sam.just@inktank.com>

diff --git a/doc/rados/operations/pg-states.rst b/doc/rados/operations/pg-states.rst
index eb0e298e2882a37797ae5dabe3cc84542182a398..8ba92ac02674456e0f6dfe9d09defac33f97945b 100644 (file)
--- a/doc/rados/operations/pg-states.rst
+++ b/doc/rados/operations/pg-states.rst
@@ -70,3 +70,7 @@ map is ``active + clean``.
 *Remapped*
   The placement group is temporarily mapped to a different set of OSDs from what
   CRUSH specified.
+
+*Undersized*
+  The placement group fewer copies than the configured pool replication level.
+