Transcript Network Management Session 1 Network Basics

COMP3122
Network Management
Richard Henson
February 2012
Week 2: Installing a
Network Server
 Objectives
– Describe each of the network operating
system types used in organisations
– Explain how to plan for installation of a
network operating system
– Effectively install a network server
operating system on a computer
Two realistic choices…



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A breed of Windows?
A breed of Unix…
Both covered briefly through
COMP2122
Planning for a network
covered in a future lecture
Historic Look at Microsoft
Network Operating Systems

Microsoft
– Windows NT 4 Server (1996)
– Windows 2000 Server series (1999)
– Windows 2003 Server, Enterprise Server,
Data Centre Server, etc…. (2003-7)
– Windows 2008 Server, Enterprise Server,
Data Centre Server, etc…. (2008-continues)
Available UNIX Network
Operating Systems

Various breeds of Unix (e.g.)
– SCO Unix
– HP-UX
– Sun Solaris

Various implementations of Linux
–
–
–
–
Ubuntu (“humanity towards others”)
Red Hat (redhat.com)
Mandrake (now Mandriva)
SuSe/Novell (now Attachmate)
Which is best?

Nice quote from a blogger:

“Windows people will do windows and
Unix people will do Unix, and neither the
twain shall ever meet (publicly) and no
amount of discourse will eradicate one
or the other.”
Which to choose?

Network should serve the needs of the
organisation
– management of resources could be best suited by a
breed of Windows Server or Unix…

Merits of breed of Unix/Linux :
» excellent for security, stability and fault tolerance provided that it
is set up properly
» also good implementation of most network management
functions

Merits of Windows 2003/2008 Server:
» very easy to administer
» excellent online & telephone support
» also good implementation of most network management
functions
Not just about the
software…

Also about understanding of the required
functionality of a NOS
– and how to configure & control the delivery of that
functionality to users

Windows quicker to roll out…
– functionality and management easier to pick up
– less fuss from a teaching/learning perspective..
– BUT principles of configuration & control apply
equally to Unix
Which choice within a
Windows Server set up?

Several options presented, to cater for a
range of network environments:
– Windows Server
– Windows Advanced Server
– Windows Datacenter Server

Important to establish which is most
appropriate beforehand…
– http://www.microsoft.com/windowsserver2003/e
valuation/features/compareeditions.mspx
Preparation for Installation:
client matters (1)

Users work at clients…
– smooth connectivity between client and
chosen server essential…

Which software on client machines?
– which operating system?
– which applications?
Preparation for Installation:
client matters (2)

Upgrade of server could affect clients
– latter may not readily interface as well with more
recent versions of the NOS
– e.g. very old (pre-2000) Windows clients couldn’t
work with active directory

Consequence could be a client upgrade
as well
Preparation for Installation:
server hardware

NOS delivers functionality
– Choice of server os should always be made first…
– make sure that CPU, RAM, etc. will be adequate
to run the NOS efficiently:
» now
» in two years time…

As much information as possible needs to be
gathered about hardware used in the server:
– software tools MAY assist with this process
Hardware compatibility
 Choose
carefully! Don’t assume
anything (!)
– you may be surprised
– you could well be disappointed!
 Microsoft
(or any other NOS
supplier) should provide a
hardware compatibility list (HCL)
– all hardware/peripherals checked against
the list
Importance of the HCL


Hardware manufacturers may have their
drivers on the Windows Server disk
If not,…
– (1) hardware is on the HCL, and the manufacturer
will have written software you can download…
– If the hardware is not on either list, it
cannot be used
» this DOES happen!
» don’t get caught out!!
Preparation for Installation:
RAM

Depends on the server configuration
chosen…
– http://www.microsoft.com/windowsserver2003/eval
uation/features/compareeditions.mspx

As regards RAM:
– domain controllers will require more…
– ECC (72-bit) memory [Error Correcting Code] recd
» detects & corrects memory errors
Preparation for Installation:
Motherboard


Motherboard options controlled by BIOS
settings
BIOS should provide an option to…
– support network booting
(PXE – Preboot Execution Environment)
PXE also very useful for clients
- support for RAID devices
Importance of
“Plug-and-Play”

Detection and software installation for
hardware components automatic
– manual install could get the wrong
version…
– not a good idea!

BIOS settings can be used for plug-andplay and interrupt reservations
Preparation for Installation:
Secondary Storage

As much as possible!
– allow extra for fault tolerance
Mirroring/duplexing/RAID 5?
 Whole network server set-up should also
have a backup in another location

– essential for network availability
– disaster recovery and business continuity are
important strategic matters…
Preparation for Installation:
media for software

Setup files for NOS usually held on CD:
– server BIOS should boot direct from CD-ROM
– otherwise, or if CD corrupted, can still use floppy
disks to load essential components

Drivers for hardware not on HCL likely to be
found separately:
– on CD-ROM
– on manufacturers website

All non-HCL drivers should be close at hand!
Preparation for Installation:
Hard Disk Partitioning
Hard disks must be partitioned before
any formatting is possible
 Normal to plan for several partitions:

– one for booting
– one for system files (could be the same as
the boot partition)
– one for user data
– one for applications

Partition data should be backed up…
Preparation for Installation:
Choice of File System


FAT32 (share security) or NTFS (file
security)
Nowadays, NTFS is increasingly the norm
– more efficient management for partitions
greater than 2 Gb
– on a network, always a good idea to settle on a
file system with security control at individual file
level
– otherwise, users can “run amok”
Client-Server and
Microsoft “domains”
Not the same as DNS domains
 Really just another way of saying LAN
or client-server network
 Domains are “server controlled”

– but server needs to be elevated to domain
controller status
– needs to install “DNS server”
Domains and Active Directory

Active Directory…
– logically connects servers together
– servers create domains…
– can use connections between servers to
model the DNS system on a Microsoft
network

But things can go wrong…
– knowledge of DNS servers required
Internet Domain Naming


An attempt to give logical names to
computers directly hooked up to the Internet
First defined back in 1983, through three
early RFCs…
– 881: The Domain Names Plan and Schedule
(revised, 897, 921)
– 882: CONCEPTS and FACILITIES (revised, 1034)
– 883: IMPLEMENTATION and SPECIFICATION
(revised, 1035)
The DNS System

First defined in RFC 1101:


First recognisable as x.y.z format through
RFC 1183:


“DNS Encoding of Network Names and Other Types”
“New DNS RR Definitions”
Explained including IANA (administration of
first level domains) through RFC 1591 (1994)

“Domain Name System Structure and Delegation”
DNS and DNS Zones
The DNS system is hierarchical
 A DNS Zone is defined as:
“… a portion of the global Domain
Name System (DNS)
namespace for which
administrative responsibility has
been delegated”

– it refers to the lower level domains
logically connected to any one
particular root domain (e.g. .us or
.com)
z
y
a
x
DNS entry x.y.z
DNS Zone: z
Computers within
z zone: a, x and y
Naming a Server within
a DNS Zone

Windows 2003 Servers promoted to
domain controllers are assumed to be
part of the DNS
– named accordingly within a hierarchy of
domain names
– DNS Server needs to be installed at this
point…
» assists Active Directory with domain name record
keeping
» provides options for storing DNS/IP address pairs
WINS, DNS, and
IP addressing

Older versions of Windows used
“Windows Internet Naming Service”
– look up service including NetBIOS names
and corresponding IP addresses

Now, DNS is increasingly replacing
WINS:
– DNS server manages access to network
name/IP address look up
Managing Domain Users


Active Directory installed when server
promoted to domain controller
Users gain access via client machines
– to even enable user log on, a client machine must
have an account in that domain
– client details stored in active directory

User must have a domain account
– details stored in “Active Directory”…
– entry in database of usernames/passwords
essential for successful login match
Post-Installation
Traps & Errors
 Most
common problem:
– files become corrupt
 This
will mean that the system boot
up process will be suspended
indefinitely as the system looks in
vain for the missing file
Correcting
Installation Errors

Each NOS should have a system to allow
recovery from a failed installation
– With Windows Server, it is “recovery console”

Such a “recovery” system should allow the
system to reboot to at least a command
prompt
– allowing the necessary file(s) to be re-installed…

The computer should then again boot up
satisfactorily
Installing Clients

Will be necessary if:
– Existing client software not compatible with
server-side or is upgraded for other
reasons
– Existing client software becomes faulty or
will not connect to the domain
– New computer to be added to the domain
Automatic Installations
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The first server on the network should always
be installed manually
However, NOSs allow capabilities for the
“automatic” installation of clients
This means that all the questions that are
asked by the installation process must be
answered on a text file or “script” that can be
accessed during the automatic install
– with Windows 2000/3 this is known as
UNATTEND.TXT
More about Windows
“Automatic” Installation

Several possibilities:
– RIS (Remote Installation Service)
»
»
»
»
Windows 2000/3 installation files
“Unattend” Scripts
All provided on a server (RIS server)
Supports PXE (network boot option in BIOS)
– SYSPREP
» “cloning” or “imaging” tool
» Just copy all folders and files directly from a prototype (!)
Configuration of the
Network environment


NOS should allow options to add or remove
network services and components
If the NOS is really good, such
reconfigurations will not even require a reboot!
– e.g. breeds of Unix (no registry)

Because the registry needs to be reconfigured
and reread, Windows 2000/3 does often
require a reboot when new hardware is
added…
Upgrading the Server
Environment…


Rather than starting again, with a completely
new setup, it may be necessary to upgrade
an existing facility.
If the network is being upgraded from a
previous version, it will be necessary to
migrate settings and data into the new
environment
– essential that such data is safely backed up to
tape drive or other safe location before the
upgrade begins
Dual Boot Systems

Two different operating systems held on two
system partitions
– one of the system partitions could (for simplicity)
be a floppy disk or USB drive

Most usual with network clients, interfacing
with two separate NOSs
– always boot into one operating system (boot
partition)
– then offered (via menu) a choice of system
partition to be loaded into memory
Updating Drivers


NOT a good idea to remove a driver from the
system until there is evidence that the
replacement actually works!
Advised procedure:
– disable the existing driver
– either: use the Add/Remove Hardware wizard to
find and install the new driver
– or: restart the computer and allow “plug and play”
to find and install the new driver
Ensuring that a driver is
“authorised”
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Authorised drivers are “signed” by the
manufacturer
The “digital signature” can be read by any
computer running a recent version of Windows
If a driver doesn’t have an appropriate signature
– error message “pop up” appears on the screen

The driver could still be installed, but with no
signature there is no guarantee that it will work!
Adding Manufacturers
Improvements to the NOS


Networking software continually being
updated, optimised, and improved by
manufacturers
Improvements released as:
– New version of NOS
» complete reinstall of system
– “Service Pack”
» reinstallation of certain components and new features
» plugs to recently discovered security holes
– hotfixes
Installation of a Service Pack
An “update” command is available
 The distribution folder (including URL
for Internet downloads) should be
included
 An option to uninstall the service pack
at a later date is included and
recommended
 A wizard manages the whole process

The End