update sources to v12.1.1

[ceph.git] / ceph / doc / cephfs / administration.rst

diff --git a/ceph/doc/cephfs/administration.rst b/ceph/doc/cephfs/administration.rst
index 23bd5fc6a991ed222b42b1b7117166eba01b7be8..f4976cfa2dfc7d5527527db3308108a8f6706870 100644 (file)
--- a/ceph/doc/cephfs/administration.rst
+++ b/ceph/doc/cephfs/administration.rst
@@ -81,17 +81,29 @@ These commands act on specific mds daemons or ranks.
 
 ::
 
-    mds fail <gid/name/role
+    mds fail <gid/name/role>
 
-This command deactivates an MDS causing it to flush its entire journal to
-backing RADOS objects and close all open client sessions. Deactivating an MDS
-is primarily intended for bringing down a rank after reducing the number of
-active MDS (max_mds).
+Mark an MDS daemon as failed.  This is equivalent to what the cluster
+would do if an MDS daemon had failed to send a message to the mon
+for ``mds_beacon_grace`` second.  If the daemon was active and a suitable
+standby is available, using ``mds fail`` will force a failover to the standby.
+
+If the MDS daemon was in reality still running, then using ``mds fail``
+will cause the daemon to restart.  If it was active and a standby was
+available, then the "failed" daemon will return as a standby.
 
 ::
 
     mds deactivate <role>
 
+Deactivate an MDS, causing it to flush its entire journal to
+backing RADOS objects and close all open client sessions. Deactivating an MDS
+is primarily intended for bringing down a rank after reducing the number of
+active MDS (max_mds).
+
+Use ``mds deactivate`` in conjunction with adjustments to ``max_mds`` to
+shrink an MDS cluster.  See :doc:`/cephfs/multimds`
+
 ::
 
     tell mds.<daemon name>