Data Movers in Celerra CFS-14

The project that I am working on involves Celerra, Symmetrix and
Connectrix. Some questions that I have related to Celerra:

1. How is the data mover mapped to a storage space. Celerra has 14
data movers and Symmetrix contain disks for storage but how are disks
mapped to the data movers?

2. Celerra CFS-14 contains data movers that act as file servers. What
is this file server/data mover, is it a hardware, an application or an
operating system.

3. Data Mover has an operating system (DART) of its own but does
Celerra has its own OS. If not, then how is the failover protection of
Data Movers, configuration and management done? Is Celerra CFS-14 just
a cabinet that contains Data Movers, control stations and Power
supplies.

4. Data Movers are somehow connected to the storage disks but how is
the NAS device (Celerra CFS 14 containing Data Movers) connected to the
client machines which require transfer and access of files.

5. Does a file server has a file system of its own. Data Mover acts as
a file server and it has an operating system DART. Each Data Mover has
a file system of its own?

Thanks in advance