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+Feature
+-------
+
+HA support for NFS-ganesha.
+
+Summary
+-------
+
+Automated resource monitoring and fail-over of the ganesha.nfsd in a
+cluster of GlusterFS and NFS-Ganesha servers.
+
+Owners
+------
+
+Kaleb Keithley
+
+Current status
+--------------
+
+Implementation is in progress.
+
+Related Feature Requests and Bugs
+---------------------------------
+
+-   [Gluster CLI for
+    Ganesha](Features/Gluster_CLI_for_ganesha "wikilink")
+-   [Upcall Infrastructure](Features/Upcall-infrastructure "wikilink")
+
+Detailed Description
+--------------------
+
+The implementation uses the Corosync and Pacemaker HA solution. The
+implementation consists of three parts:
+1.  a script for setup and
+teardown of the clustering.
+2.  three new Pacemaker resource agent files,
+and
+3.  use of the existing IPaddr and Dummy Pacemaker resource agents
+for handling a floating Virtual IP address (VIP) and putting the
+ganesha.nfsd into Grace.
+
+The three new resource agents are tentatively named ganesha\_grace,
+ganesha\_mon, and ganesha\_nfsd.
+
+The ganesha\_nfsd resource agent is cloned on all nodes in the cluster.
+Each ganesha\_nfsd resource agent is responsible for mounting and
+unmounting a shared volume used for persistent storage of the state of
+all the ganesha.nfsds in the cluster and starting the ganesha.nfsd
+process on each node.
+
+The ganesha\_mon resource agent is cloned on all nodes in the cluster.
+Each ganesha\_mon resource agent monitors the state of its ganesha.nfsd.
+If the daemon terminates for any reason it initiates the move of its VIP
+to another node in the cluster. A Dummy resource agent is created which
+represents the dead ganesha.nfsd. The ganesha\_grace resource agents use
+this resource to send the correct hostname in the dbus event they send.
+
+The ganesha\_grace resource agent is cloned on all nodes in the cluster.
+Each ganesha\_grace resource agent monitors the states of all
+ganesha.nfsds in the clustger. If any ganesha.nfsd has died, it sends a
+DBUS event to its own ganesha.nfsd to put it into Grace.
+
+IPaddr and Dummy resource agents are created on each node in the
+cluster. Each IPaddr resource agent has a unique name derived from the
+node name (e.g. mynodename-cluster\_ip-1) and manages an associated
+virtual IP address. There is one virtual IP address for each node.
+Initially each IPaddr and its virtual IP address is tied to its
+respective node, and moves to another node when its ganesha.nfsd dies
+for any reason. Each Dummy resource agent has a unique name derived from
+the node name (e.g. mynodename-trigger\_ip-1) is used to ensure the
+proper order of operations, i.e. move the virtual IP, then send the dbus
+signal.
+
+N.B. Originally fail-back was outside the scope for the Everglades
+release. After a redesign we got fail-back for free. If the ganesha.nfsd
+is restarted on a node its virtual IP will automatically fail back.
+
+Benefit to GlusterFS
+--------------------
+
+GlusterFS is expected to be a common storage medium for NFS-Ganesha
+NFSv4 storage solutions. GlusterFS has its own built-in HA feature.
+NFS-Ganesha will ultimately support pNFS, a cluster-aware version of
+NFSv4, but does not have its own HA functionality. This will allow users
+to deploy HA NFS-Ganesha.
+
+Scope
+-----
+
+TBD
+
+### Nature of proposed change
+
+TBD
+
+### Implications on manageability
+
+Simplifies setup of HA by providing a supported solution with a recipe
+for basic configuration plus an automated setup.
+
+### Implications on presentation layer
+
+None
+
+### Implications on persistence layer
+
+A small shared volume is required. The NFSganesha resource agent mounts
+and unmounts the volume when it starts and stops.
+
+This volume is used by the ganesha.nfsd to persist things like its lock
+state and is used by another ganesha.nfsd after a fail-over.
+
+### Implications on 'GlusterFS' backend
+
+A small shared volume is required. The NFSganesha resource agent mounts
+and unmounts the volume when it starts and stops.
+
+This volume must be created before HA setup is attempted.
+
+### Modification to GlusterFS metadata
+
+None
+
+### Implications on 'glusterd'
+
+None
+
+How To Test
+-----------
+
+TBD
+
+User Experience
+---------------
+
+The user experiences is intended to be as seamless and invisible as
+possible. There are a few new CLI commands added that will invoke the
+setup script. The Corosync/Pacemaker setup takes about 15-30 seconds on
+a four node cluster, so there is a short delay between invoking the CLI
+and the cluster being ready.
+
+Dependencies
+------------
+
+GlusterFS CLI and Upcall Infrastructure (see related features).
+
+Documentation
+-------------
+
+<Status of development - Design Ready, In development, Complete> In
+development
+
+Comments and Discussion
+-----------------------
+
+The feature page is not complete as yet. This will be updated regularly.