update sources to ceph Nautilus 14.2.1

[ceph.git] / ceph / doc / cephfs / file-layouts.rst

diff --git a/ceph/doc/cephfs/file-layouts.rst b/ceph/doc/cephfs/file-layouts.rst
index 4124e1e061df22339121f92ffb2ac1d567012488..5334765136a509939a422d7ad7224b7623002466 100644 (file)
--- a/ceph/doc/cephfs/file-layouts.rst
+++ b/ceph/doc/cephfs/file-layouts.rst
@@ -38,7 +38,7 @@ object_size
 
     RADOS enforces a configurable limit on object sizes: if you increase CephFS
     object sizes beyond that limit then writes may not succeed.  The OSD
-    setting is ``rados_max_object_size``, which is 128MB by default.
+    setting is ``osd_max_object_size``, which is 128MB by default.
     Very large RADOS objects may prevent smooth operation of the cluster,
     so increasing the object size limit past the default is not recommended.
 
@@ -99,7 +99,9 @@ Layout fields are modified using ``setfattr``:
 .. code-block:: bash
 
     $ ceph osd lspools
-    0 rbd,1 cephfs_data,2 cephfs_metadata,
+    0 rbd
+    1 cephfs_data
+    2 cephfs_metadata
 
     $ setfattr -n ceph.file.layout.stripe_unit -v 1048576 file2
     $ setfattr -n ceph.file.layout.stripe_count -v 8 file2
@@ -127,7 +129,7 @@ Clearing layouts
 ----------------
 
 If you wish to remove an explicit layout from a directory, to revert to
-inherting the layout of its ancestor, you can do so:
+inheriting the layout of its ancestor, you can do so:
 
 .. code-block:: bash
 
@@ -201,15 +203,27 @@ directories do not have layouts set:
 
     
 Adding a data pool to the MDS
----------------------------------
+-----------------------------
 
 Before you can use a pool with CephFS you have to add it to the Metadata Servers.
 
 .. code-block:: bash
 
     $ ceph fs add_data_pool cephfs cephfs_data_ssd
-    # Pool should now show up
-    $ ceph fs ls
+    $ ceph fs ls  # Pool should now show up
     .... data pools: [cephfs_data cephfs_data_ssd ]
 
 Make sure that your cephx keys allows the client to access this new pool.
+
+You can then update the layout on a directory in CephFS to use the pool you added:
+
+.. code-block:: bash
+
+    $ mkdir /mnt/cephfs/myssddir
+    $ setfattr -n ceph.dir.layout.pool -v cephfs_data_ssd /mnt/cephfs/myssddir
+
+All new files created within that directory will now inherit its layout and place their data in your newly added pool. 
+
+You may notice that object counts in your primary data pool (the one passed to ``fs new``) continue to increase, even if files are being created in the pool you added.  This is normal: the file data is stored in the pool specified by the layout, but a small amount of metadata is kept in the primary data pool for all files.
+
+