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+
+Supported Features of the Kernel Driver
+========================================
+The kernel driver is developed separately from the core ceph code, and as
+such it sometimes differs from the FUSE driver in feature implementation.
+The following details the implementation status of various CephFS features
+in the kernel driver.
+
+Inline data
+-----------
+Inline data was introduced by the Firefly release. This feature is being
+deprecated in mainline CephFS, and may be removed from a future kernel
+release.
+
+Linux kernel clients >= 3.19 can read inline data and convert existing
+inline data to RADOS objects when file data is modified. At present,
+Linux kernel clients do not store file data as inline data.
+
+See `Experimental Features`_ for more information.
+
+Quotas
+------
+Quota was first introduced by the hammer release. Quota disk format got renewed
+by the Mimic release. Linux kernel clients >= 4.17 can support the new format
+quota. At present, no Linux kernel client support the old format quota.
+
+See `Quotas`_ for more information.
+
+Multiple file systems within a Ceph cluster
+-------------------------------------------
+The feature was introduced by the Jewel release. Linux kernel clients >= 4.7
+can support it.
+
+See `Experimental Features`_ for more information.
+
+Multiple active metadata servers
+--------------------------------
+The feature has been supported since the Luminous release. It is recommended to
+use Linux kernel clients >= 4.14 when there are multiple active MDS.
+
+Snapshots
+---------
+The feature has been supported since the Mimic release. It is recommended to
+use Linux kernel clients >= 4.17 if snapshot is used.
+
+.. _Experimental Features: ../experimental-features
+.. _Quotas: ../quota