doc: add notes on using "ceph fs new"

Signed-off-by: John Spray <john.spray@redhat.com>

diff --git a/doc/cephfs/createfs.rst b/doc/cephfs/createfs.rst
new file mode 100644 (file)
index 0000000..5f791bc
--- /dev/null
+++ b/doc/cephfs/createfs.rst
@@ -0,0 +1,62 @@
+========================
+Create a Ceph filesystem
+========================
+
+.. tip::
+
+    The ``ceph fs new`` command was introduced in Ceph 0.84.  Prior to this release,
+    no manual steps are required to create a filesystem, and pools named ``data`` and
+    ``metadata`` exist by default.
+
+    The Ceph command line now includes commands for creating and removing filesystems,
+    but at present only one filesystem may exist at a time.
+
+A Ceph filesystem requires at least two RADOS pools, one for data and one for metadata.
+When configuring these pools, you might consider:
+
+- Using a higher replication level for the metadata pool, as any data
+  loss in this pool can render the whole filesystem inaccessible.
+- Using lower-latency storage such as SSDs for the metadata pool, as this
+  will directly affect the observed latency of filesystem operations
+  on clients.
+
+Refer to :doc:`/rados/operations/pools` to learn more about managing pools.  For
+example, to create two pools with default settings for use with a filesystem, you
+might run the following commands:
+
+.. code:: bash
+
+    $ ceph osd pool create cephfs_data <pg_num>
+    $ ceph osd pool create cephfs_metadata <pg_num>
+
+Once the pools are created, you may enable the filesystem using the ``fs new`` command:
+
+.. code:: bash
+
+    $ ceph fs new <fs_name> <metadata> <data>
+
+For example:
+
+.. code:: bash
+
+    $ ceph fs new cephfs cephfs_metadata cephfs_data
+    $ ceph fs ls
+    name: cephfs, metadata pool: cephfs_metadata, data pools: [cephfs_data ]
+
+Once a filesystem has been created, your MDS(s) will be able to enter
+an *active* state.  For example, in a single MDS system:
+
+.. code:: bash
+
+    $ ceph mds stat
+    e5: 1/1/1 up {0=a=up:active}
+
+Once the filesystem is created and the MDS is active, you are ready to mount
+the filesystem:
+
+.. toctree:: 
+       :maxdepth: 1
+
+       Mount Ceph FS <kernel>
+       Mount Ceph FS as FUSE <fuse>
+

diff --git a/doc/cephfs/index.rst b/doc/cephfs/index.rst
index 8c6da5ec09d2d4a38486b76637f2192075cab111..7821701f5e0bb0edface8419d87b4d356b5eb8de 100644 (file)
--- a/doc/cephfs/index.rst
+++ b/doc/cephfs/index.rst
@@ -54,13 +54,14 @@ least one :term:`Ceph Metadata Server` running.
        </td><td><h3>Step 2: Mount Ceph FS</h3>
 
 Once you have a healthy Ceph Storage Cluster with at least
-one Ceph Metadata Server, you may mount your Ceph Filesystem.
+one Ceph Metadata Server, you may create and mount your Ceph Filesystem.
 Ensure that you client has network connectivity and the proper
 authentication keyring.
 
 .. toctree:: 
        :maxdepth: 1
 
+       Create Ceph FS <createfs>
        Mount Ceph FS <kernel>
        Mount Ceph FS as FUSE <fuse>
        Mount Ceph FS in fstab <fstab>