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+=========================
+Create a Ceph file system
+=========================
+
+Creating pools
+==============
+
+A Ceph file system 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 file system inaccessible.
+- Using lower-latency storage such as SSDs for the metadata pool, as this will
+  directly affect the observed latency of file system operations on clients.
+- The data pool used to create the file system is the "default" data pool and
+  the location for storing all inode backtrace information, used for hard link
+  management and disaster recovery. For this reason, all inodes created in
+  CephFS have at least one object in the default data pool. If erasure-coded
+  pools are planned for the file system, it is usually better to use a
+  replicated pool for the default data pool to improve small-object write and
+  read performance for updating backtraces. Separately, another erasure-coded
+  data pool can be added (see also :ref:`ecpool`) that can be used on an entire
+  hierarchy of directories and files (see also :ref:`file-layouts`).
+
+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 file system, you
+might run the following commands:
+
+.. code:: bash
+
+    $ ceph osd pool create cephfs_data
+    $ ceph osd pool create cephfs_metadata
+
+Generally, the metadata pool will have at most a few gigabytes of data. For
+this reason, a smaller PG count is usually recommended. 64 or 128 is commonly
+used in practice for large clusters.
+
+.. note:: The names of the file systems, metadata pools, and data pools can
+          only have characters in the set [a-zA-Z0-9\_-.].
+
+Creating a file system
+======================
+
+Once the pools are created, you may enable the file system 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 file system 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
+    cephfs-1/1/1 up {0=a=up:active}
+
+Once the file system is created and the MDS is active, you are ready to mount
+the file system.  If you have created more than one file system, you will
+choose which to use when mounting.
+
+  - `Mount CephFS`_
+  - `Mount CephFS as FUSE`_
+  - `Mount CephFS on Windows`_
+
+.. _Mount CephFS: ../../cephfs/mount-using-kernel-driver
+.. _Mount CephFS as FUSE: ../../cephfs/mount-using-fuse
+.. _Mount CephFS on Windows: ../../cephfs/ceph-dokan
+
+If you have created more than one file system, and a client does not
+specify a file system when mounting, you can control which file system
+they will see by using the `ceph fs set-default` command.
+
+Adding a Data Pool to the File System 
+-------------------------------------
+
+See :ref:`adding-data-pool-to-file-system`.
+
+
+Using Erasure Coded pools with CephFS
+=====================================
+
+You may use Erasure Coded pools as CephFS data pools as long as they have overwrites enabled, which is done as follows:
+
+.. code:: bash
+
+    ceph osd pool set my_ec_pool allow_ec_overwrites true
+    
+Note that EC overwrites are only supported when using OSDS with the BlueStore backend.
+
+You may not use Erasure Coded pools as CephFS metadata pools, because CephFS metadata is stored using RADOS *OMAP* data structures, which EC pools cannot store.
+