Chapter 1. All About NAS and FreeNAS
The first chapter is a high level look at Network
Attached Storage (NAS), and more specifically, the
FreeNAS software. We will cover the basic idea
behind NAS and the philosophy of the FreeNAS
server. This chapter is less hands-on than the others
in this book, but it is important to understand the
concepts of Network Attached Storage and where the
FreeNAS server fits into your business. The main
topics for this chapter include:
What is Network Attached Storage?
What is FreeNAS?
What are the features of FreeNAS?
What does FreeNAS do for me and my
business?
Network Attached Storage
In the mid 80s, two popular computer companies
independently started to work on ways to access
files, over the network, on another computer as if the
hard drive of that remote computer was attached to
the local machine. These two companies were Sun
Microsystems and Microsoft. The Sun Microsystems
method, which was for their UNIX operating system,
is known as the Network File System (NFS) and was
subsequently implemented in almost all versions of
the UNIX operating system including Linux. The
Microsoft solution (which they actually joint developed
with IBM in the initial stages) became known as SMB
(Server Message Block) but in later years was
renamed as the Common Internet File System
(CIFS).

with high speed local networks and the access
protocols of CIFS and NFS, a new kind of storage
solution has appeared: Network Attached Storage or
NAS for short. A NAS server is similar to a traditional
file server in many ways, especially in respects to the
hardware side of the server. But a NAS server is
much more specialized than a traditional office or
departmental server in that it only provides access to
storage via the network. It is not designed to run other
applications such as databases or email servers,
which other types of server might. Normally, NAS
servers don't require a keyboard, mouse or monitor
permanently connected to them and for day-to-day
administration, a web interface is used instead.
Here is an example of the FreeNAS web interface:
To access the data on the server, a typical NAS will
support multiples access protocols and so allow
Microsoft Windows clients, Apple OS X clients, and
UNIX (including Linux) clients to connect and use the
data on the server.
NAS servers normally contain one or more hard
disks, and these hard disks can be combined to
create large contiguous areas of storage or used in a
way to create redundancy. In a redundancy set-up, if a
hard disk fails then the system keeps working and
your data isn't lost.
NAS servers come in all shapes and sizes. There are
several companies that offer compact NAS servers
with an embedded operating system and space for
maybe two hard drives. These units are relatively

network environment and so allows diverse
types of computers to connect and use its
storage.
Therefore, NAS has an overall lower cost than a
traditional server while allowing for expansion and
increasing availability and security.
This book focuses on one implementation of NAS
called FreeNAS (Free Network Attached Storage),
which will turn a normal PC or server into a NAS.
What is FreeNAS?
FreeNAS is free piece of software that turns a PC
into a NAS server. It supports connections from
Microsoft Windows, Apple OS X, Linux, and
FreeBSD. It supports hard disk redundancy, has a
simple web administration interface, and modest
system requirements.
FreeNAS is what is known as an embedded
operating system. This means it is compact, efficient,
and dedicated to just one task, in this case, NAS.
Once FreeNAS is installed on a PC, the PC
becomes a dedicated NAS, it can't do other general
tasks at the same time.
To use FreeNAS, you need to download a copy of the
software from and boot it on
the computer you want to make a NAS. We shall look
at this in more detail in the next chapter.
FreeNAS comes in two variations; the live CD and an
installable kit. The live CD boots the machine as a
NAS and uses a floppy disk or USB flash drive to
store the configuration information. The installable

Distribution (BSD) branch. FreeNAS is
built on top of and relies on FreeBSD.
Because of the high level of synergy
between FreeNAS and FreeBSD,
chapters 9 and 10 have been written to
help you in troubleshooting problems on
your FreeNAS and will deal with low
level commands for the FreeBSD
operating system.