From: Sage Weil <sage@newdream.net>
Date: Tue, 20 Apr 2021 14:07:03 +0000 (-0400)
Subject: doc/cephadm: document _no_schedule label
X-Git-Tag: v17.1.0~2185^2~3
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=c7dae3ceb78999e4b06d108a43cedf2b2693c273;p=ceph.git

doc/cephadm: document _no_schedule label

Signed-off-by: Sage Weil <sage@newdream.net>
---

diff --git a/doc/cephadm/host-management.rst b/doc/cephadm/host-management.rst
index edf6772d40d6..a586df246ec2 100644
--- 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 26533544c0b2..e6952cebbded 100644
--- 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
 -------------------