From: Patrick Donnelly <pdonnell@redhat.com>
Date: Fri, 6 Apr 2018 03:06:29 +0000 (-0700)
Subject: doc: outline steps to take CephFS fs down
X-Git-Tag: v13.1.0~309^2
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=9aa13bf0b0bf20b4fcf4949af60ebfff1e8fea0a;p=ceph.git

doc: outline steps to take CephFS fs down

Fixes: https://tracker.ceph.com/issues/23427

Signed-off-by: Patrick Donnelly <pdonnell@redhat.com>
---

diff --git a/doc/cephfs/administration.rst b/doc/cephfs/administration.rst
index bcba78de375..2b70fa0e872 100644
--- a/doc/cephfs/administration.rst
+++ b/doc/cephfs/administration.rst
@@ -74,6 +74,22 @@ appear to be eg. exabytes in size, causing load on the MDS as it tries
 to enumerate the objects during operations like stats or deletes.
 
 
+Taking the cluster down
+-----------------------
+
+Taking a CephFS cluster down is done by reducing the number of ranks to 1,
+setting the cluster_down flag, and then failing the last rank. For example:
+
+::
+    ceph fs set <fs_name> max_mds 1
+    ceph mds deactivate <fs_name>:1 # rank 2 of 2
+    ceph status # wait for rank 1 to finish stopping
+    ceph fs set <fs_name> cluster_down true
+    ceph mds fail <fs_name>:0
+
+Setting the ``cluster_down`` flag prevents standbys from taking over the failed
+rank.
+
 Daemons
 -------