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Introduction to Manila Shared Filesystem Management Service
===========================================================

Manila is the file share service project for OpenStack. Manila provides the
management of file shares for example, NFS and CIFS as a core service to
OpenStack. Manila currently works with NetApp, Red Hat storage (GlusterFS)
and EMC VNX, as well as on a base Linux NFS or Samba server. There are
a number of concepts that will help in better understanding of the
solutions provided by Manila. One aspect can be to explore the
different service possibilities provided by Manila.

Manila, depending on the driver, requires the user by default to create a
share network using neutron-net-id and neutron-subnet-id (GlusterFS native
driver does not require it). After creation of the share network, the user
can proceed to create the shares. Users in Manila can configure multiple
back-ends just like Cinder. Manila has a share server assigned to every
tenant. This is the solution for all back-ends except for GlusterFS. The
customer in this scenario is prompted to create a share server using neutron
net-id and subnet-id before even trying to create a share.

The current low-level services available in Manila are:

- manila-api: The manila-api service is a service that authenticates and
  routes requests throughout the Shared Filesystem service.

- manila-scheduler: The manila-scheduler is responsible for
  scheduling/routing requests to the appropriate share service. It does that
  by picking one back-end while filtering all except one back-end.

- manila-share: The manila-share service is responsible for managing Shared
  File Service devices, specifically the back-end devices.