doc/cephadm: document _no_schedule label

Signed-off-by: Sage Weil <sage@newdream.net>
(cherry picked from commit c7dae3ceb78999e4b06d108a43cedf2b2693c273)

diff --git a/doc/cephadm/host-management.rst b/doc/cephadm/host-management.rst
index edf6772d40d6f7b374f930dcfc6becf1956709a2..a586df246ec2b5380d48332f0dd53925dcc2445c 100644 (file)
--- a/doc/cephadm/host-management.rst
+++ b/doc/cephadm/host-management.rst
@@ -117,7 +117,21 @@ To remove a label, run::
 
   ceph orch host label rm my_hostname my_label
 
-  
+
+.. _cephadm-special-host-labels:
+
+Special host labels
+-------------------
+
+The following host labels have a special meaning to cephadm.  All start with ``_``.
+
+* ``_no_schedule``: *Do not schedule or deploy daemons on this host*.
+
+  This label prevents cephadm from deploying daemons on this host.  If it is added to
+  an existing host that already contains Ceph daemons, it will cause cephadm to move
+  those daemons elsewhere (except OSDs, which are not removed automatically).
+
+
 Maintenance Mode
 ================
 

diff --git a/doc/cephadm/service-management.rst b/doc/cephadm/service-management.rst
index 26533544c0b2c6d846c5c9e005af66904969d989..e6952cebbded5f5c3789cd3c553017942d2c7ccc 100644 (file)
--- a/doc/cephadm/service-management.rst
+++ b/doc/cephadm/service-management.rst
@@ -132,6 +132,10 @@ For the orchestrator to deploy a *service*, it needs to know where to deploy
 specification.  Placement specifications can either be passed as command line arguments
 or in a YAML files.
 
+.. note::
+
+   cephadm will not deploy daemons on hosts with the ``_no_schedule`` label; see :ref:`cephadm-special-host-labels`.
+
 Explicit placements
 -------------------