NAS Last Update 2012.03.19 1.7.0 Copyright 2000-2010 Kenneth N. Chipps Ph.D. 1

NASLast Update 2012.03.19

1.7.0

Copyright 2000-2010 Kenneth N. Chipps Ph.D. www.chipps.com

1

Objectives of This Section

• Learn– What NAS is– How to use a NAS device in a LAN

Copyright 2000-2010 Kenneth N. Chipps Ph.D. www.chipps.com 2

What is a NAS

• NAS is Network Attached Storage• In this approach data drives are taken out

of the server that holds the network operating system

• They are deployed in a box that runs a proprietary operating system that just understands serving up data


What is a NAS

• This box is entirely independent of the server’s operating system or the server itself

• Small NAS boxes is an easy and quick way to add storage to an existing network

• It can also be used to provide common storage to a small network without the bother of supporting a full network operating system such as Windows Server


What is NAS

• These boxes only do one thing, serve up data

• As such they can do this very fast• For large installations these devices go up

to a terabyte in size


Why is a NAS Used

• In a standard server based network all of the storage is in the servers

• This can produce several problems as the network grows

• First, all of the storage space is in discrete pools

• One of these can run out of space while another has too much space

• Adjusting between these is not easy


Why is a NAS Used

• Second, sharing data across platforms is difficult, as the various operating systems cannot directly talk to each other

• When NAS devices are included all or part of the storage is now in the NAS boxes

• These devices are attached directly to the LAN


Why is a NAS Used

• These devices require no licenses to use them, unlike the traditional server operating systems

• Further if you run out of storage space again, just plug in another NAS box


A NAS Box


Small v Large NAS

• A small NAS box is a standalone device that can be purchased at an office supply store

• A gateway type of NAS is used to create a much larger set of shared storage devices directly attached to the local area network this time through a NAS gateway device


Network or Internet Appliances

• Sometimes these types of boxes are called network or internet appliances instead of the more general term NAS

• When they are called this it is usually meant to relate to a special purpose NAS doing something other than general storage


Network or Internet Appliances

• Such as– Web server– Mail server– Firewall– Caching

• It does not matter what they are called as long as you understand what they are meant to do


Problems with a NAS

• NAS boxes use file oriented rather than the faster block oriented protocols to access information

• As such in some low speed LANs the protocols used, such as NFS, CIFS, or HTTP over TCP/IP can cause bottlenecks for high data transfer application such as databases


Problems with a NAS

• These are not the quickest protocols• As such they can introduce some latency

into the process• In most cases this can be solved by

throwing bandwidth at it


Lab

• Let’s find a NAS box


Documents

NAS Last Update 2012.03.19 1.7.0 Copyright 2000-2010 Kenneth N. Chipps Ph.D. 1