CompTIA Network+ Certification Study Guide part 50 doc

NETworK MANAGEMENT Keeping track of network resources and how they are assigned; maintaining, upgrading and repairing network equipment, configuring resources for opti-mal resource usage

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ExAM oBJECTIvES IN ThIS ChApTEr

INTroduCTIoN

Why do networked information systems need to be managed? Well, without

skillful and insightful management your network can quickly become out of

control What does management have to do with networking? Well, a lot The

act, manner, or practice of managing, handling, supervising, or controlling is

simply managing Take this definition and merge it with your information

systems network What do you have? Network management refers to the

activities, techniques, measures, and gear that pertain to how you operate,

administer, maintain, and condition the networked information systems to

ensure the highest availability possible within your budget The bottom line

goal here is to identify and manage network errors as soon as possible before

the users begin to notice, or, maybe even worse, your boss!

NETworK MANAGEMENT

Keeping track of network resources and how they are assigned; maintaining,

upgrading and repairing network equipment, configuring resources for

opti-mal resource usage and network performance (Voice over Internet Protocol

[VoIP]) via monitoring techniques; configuration management

documenta-tion (wiring schematics for your WAN links and local points of presence

[POP], network diagrams, baselines, policies and regulations) are all

inclu-sive to network management

How can you plan and execute replacement of critical networked

equipment, patch a router internetworking operating system image, add

Network Management

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a fiber switch to a network, and configure resources for your new office’s voice services? These can be achieved by keeping the Mean Time To Repair (MTTR) as short as possible What’s MTTR have to do with it? Well, MTTR

is part of a larger network management framework

A common way of characterizing network management functions is Fault, Configuration, Accounting, Performance, and Security (FCAPS) What are functions? Functions are sets of tasks performed in one or more

of the following:

Controlling

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Planning

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Allocating

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Deploying

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Coordinating

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Monitoring resources

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Network planning

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Frequency allocation

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Predetermined traffic routing

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Load balancing

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Cryptographic distribution

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Configuration management

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Fault management

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Security management

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Performance management

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Bandwidth management

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Route analytics

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Accounting management

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CoNFIGurATIoN MANAGEMENT

Unless you’re dealing with a small network of only a few computers, once a computer or other piece of equipment has been configured, management of the device is necessary Configuration management (CM) is a practice that

involves documentation of a device’s configuration, as well as keeping that

documentation up to date so that any future changes can be controlled and

tracked While this seems at face value like a straightforward, easy to follow

practice, it is the one that often falls by the wayside CM is useful for a

num-ber of reasons The documentation created on the network can be quickly

referenced, allowing you to identify how a device was configured, its location

on the network, and other detailed information about the device By having

this information, you can replace devices and make changes to the network

quickly

By compiling information on the components of your network, you

cre-ate an inventory that can be used to track items that need to be replaced

or upgraded Most organizations have a life cycle for computer equipment

and replace older machines every three or four years Network devices like

routers and switches may last longer, but they will eventually need to be

replaced with newer and faster equipment Keeping a database allows you to

schedule upgrades and replacements more easily, because you can monitor

details such as when the item was installed on the network and whether it

is approaching the end of its life cycle

Managing software and hardware in this manner also provides a

record of computer assets that are owned by the company This

informa-tion can be useful in budgeting replacements and determining insurance

needs If a disaster occurs, the documented information can also be used

to allow you to identify what was destroyed or damaged

In this chapter, we will see how disasters are an issue which needs to be

addressed in order to mitigate the risk they present to businesses as a whole

If a disaster occurs, the configuration information can be used to replace

damaged devices, so that the replaced devices are configured the same as

their predecessors For example, if a server was destroyed, you could replace

that server with another, give it the same name and Internet Protocol (IP)

address, and have it provide the same services Except for the time taken to

replace the server, users of the network might be unaware that a problem

even existed

CM documentation Types

Writing schematics, developing physical and logical network diagrams,

establishing baselines, creating policy, procedures, configurations, and using

regulations are all a part of configuration management documentation

What should I document? Well, many network managers and engineers

have varying opinions on this subject due to the dissimilar network

infra-structures, budget, and network services they provide But the fundamental

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aspects to concern yourself with when collecting information to document should include the following:

Physical access methods – How does your network physically connect from one office to another? Are you sharing a Token Ring (802.5) fiber network, WiMAX (802.16) across the boulevard? Maybe your network uses a mixture of transmission methods, but at what speed do they operate? These are the type of questions you will ask yourself to collect information on physical access methods so you can understand your network configuration in case you need to troubleshoot physical network access errors

Service Protocols – What protocols do you use on your servers, work-stations, data centers, routers, switches, and even on your network print-ers? Some printers’ host configuration Web portals allow administrators to remotely control link status and paper jams Knowing what kind of service protocols are on your network and documenting them will help you deter-mine what you need and what you can get rid of

Hardware devices – Have you ever scanned your network and found devices that you didn’t even know existed? Collecting information and docu-menting it can help you stay in tune with your network configuration and possibly lead you to solving errors quicker How many routers, switches, hubs, rack mounted servers, workstations, laptops, PDAs, thumb drives, power supplies, printers, networked digital pictures frames, wireless flat screens, bluetooth-enabled devices, and any other wireless devices, are on your network right now? Now that you know how many of each device you have, do you know where they are physically located at any given point in time? Do you have the vendor service tags, serial numbers, and contact information mapped to each associated device so you can effectively respond

to trouble tickets? This is a great CM piece to have documented, because you will always find that you need to locate some piece of equipment that needs repairing

Software applications – Legacy, third party, proprietary software applica-tions must all be managed effectively because many applicaapplica-tions’ software development life cycles end very quickly when your network expands or con-tracts If you aren’t in control of your software and the associated updates, you will be playing catch-up, and that’s no fun What applications are installed on your hardware devices (workstations, servers, routers, switches, firewalls, and printers)? What applications communicate between your clients and servers? Do you store all of your software in one central reposi-tory? How do your applications run? Are they server-based or client-based? How often does the software vendor release patches, upgrades, and security alerts? Do you know the current version of your applications? Asking these

questions and documenting the responses can help you answer this type

of question, “Are your routers IOS compatible with the upcoming network

switch upgrade?”

documenting Configurations

CM starts by performing an inventory of network components and

docu-menting information about each device How much data you compile is

subjective, but you should include as many specifics as possible about the

machine Information included in a database or series of documents might

include:

The date the document was last modified, so you can determine

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whether you’re looking at the most recent information

The asset number, which is a unique number that your

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tion may assign to an asset so that it can be identified within the

company A sticker may be affixed to an item so it can

easily be matched to information within a database

The name of the device, which is the name that a computer, printer,

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or other device is given so that it can be identified on a network

The IP address, which is a unique network number that identifies

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a computer or device on a Transmission Control Protocol/Internet

Protocol (TCP/IP) network

The Media Access Control (MAC) address, which is a unique

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ware number that identifies the computer on a network

The make and model, which identifies who made the device, as

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well as its model number

The serial number and product ID, which are numbers or

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numeric combinations that appear on devices They can be used to

identify a particular device when several are in one location, and

may be required when calling manufacturers, help desks, or service

representatives when a problem arises

The location, so you can determine the building, floor, and room in

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which a device is located

The person who has been issued the device This is useful when

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computers, personal digital assistants (PDAs) or other devices are

issued to a specific person This provides a contact person, and can

make it easier to locate the device

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The purchase date that indicates when the company bought the device

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The warranty information, including how long the device is under

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warranty, and whether it includes parts and labor, onsite service, and

so on

The operating system, which should include the manufacturer,

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name, and version information (for example, Microsoft Windows

2000 Professional 5.0.2195 Service Pack 4 Build 2195) This will not only indicate the operating system installed, but also whether the latest service packs have been applied

Memory that refers to the amount of physical memory installed on

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a computer This will allow you to determine whether software or upgrades to a newer operating system can be installed on a particu-lar machine

The processor type, which will often determine whether the computer

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needs to be upgraded, and also whether upgrades of software are possible

Hard disk information, including the sizes and number of hard

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disks, which is useful when replacing a redundant array of

inde-pendent disks (RAID).

Common and special software This includes the names and

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sions of major software packages that are used throughout your organization (such as Microsoft Office or Internet Explorer), as well

as applications that are used only on a single computer or only on certain machines in your company

Components installed or associated with the device, such as

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modems, Peripheral Component Interconnect cards issued with a laptop, or other components that were added after the initial pur-chase of the machine

There are a number of methods and tools available to help you acquire most of the information to be included in your hardware database Obvi-ously, the location of the device and to whom it was issued are things that

a program can’t tell you, but other information can be acquired using con-figuration utilities that come with the device or those offered by a com-puter’s operating system Some of these tools are discussed in greater detail

in Chapter 11, and not only serve as troubleshooting tools, but can be used

to acquire data about the computer being used and various devices on your network

These tools include:

ipconfig

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ifconfig

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winipcfg

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ping

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system information

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Ipconfig is a command line tool that allows you to view information

about a Microsoft Windows NT, XP, 2000, 2003, or 2008 computer’s TCP/

IP configuration On UNIX and Linux machines, a similar tool called

ifcon-fig is used to display this information By typing ipconifcon-fig at the command

line (or ifconfig on UNIX/Linux computers), you can see how each network

card or modem on a computer is configured, including the IP address,

subnet mask, and default gateway, as well as other important information

about the network adapter To view additional information including the

physical address (MAC address), Dynamic Host Configuration Protocol

(DHCP), and Domain Name System (DNS) you would type ipconfig/ALL.

Change Control documentation

One of the benefits of compiling information about devices on your network

is that it can allow you to see which devices will be affected by a network

change For example, let’s say you were planning on changing the IP address

of a router that serves as the default gateway for workstations Since these

computers use the router to connect to other portions of a network, when

this change is made, the default gateway setting of these workstations would

no longer be valid By searching your hardware database, you can determine

which computers use the router as a default gateway and will therefore be

affected by the change This allows you to see which computers will have

to have configuration settings changed so that their settings match the

router’s new IP address As you can see, one change can cause numerous

other changes across the network Because change is inevitable and

pos-sibly far reaching, it’s important to maintain information about changes

Configuration information stored in a hardware database has to be kept

up to date In addition to this, you should also maintain documentation on

changes that have been made

Change control documentation provides a record of changes that have

been made into a system, which can be used in troubleshooting problems

and upgrading systems When creating a change control document, you

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should begin by describing the change that was made and explaining why this change occurred Changes should not appear to be made for the sake of change, but must have good reasons, such as fixing security vulnerabilities, hardware no longer being supported by vendors, new functionality, or any number of other reasons The documentation should then outline how these changes were made, detailing the steps you performed

By providing details in this manner, you also create a document that provides back-out steps on how to restore a system to its previous state

At times, you will need to undo the changes and restore the system to a previous state because of issues resulting from a change In such cases, the change documentation can be used as a reference for backtracking the steps taken

The procedures you document are a valuable resource when you are recovering from a disaster and/or need to install another device or software identical to the one it’s replacing Your documentation on the steps you performed to install a component can be used to duplicate the installa-tion during a recovery procedure Because the same steps can be followed,

a computer or other device can be set up and configured identically to the one it’s replacing

wiring Schematics

Wiring schematics are simple sketches that are created before and during installation of the physical media used for computers to talk to each other These schematics are also developed while troubleshooting and deploying new Open Systems Interconnection layer 1 technology Some wiring sche-matics can be very complex and can be refined as your network architecture expands Microsoft Visio, SmartDraw, and even computer aided design soft-ware packages assist in creating your wringing schematics

The physical media such as coax cable, twisted-pair, and unshielded twisted-pair (UTP) used to connect your network are very common types

to be included when creating wiring schematics Figure 10.1 is a wiring schematic describing the pin number associated with each pair of colored wires This figure is Electronic Industries Associate/Telecommunications Industry Alliance EIA/TIA 568A/B standard for UTP cable termination (Figure 10.1)

When troubleshooting a network connection problem, remember your wiring schematics because sometimes it might be as easy as switching out some UTP cabling if the wiring in the RJ-45 connector was created incor-rectly, especially for custom length computer cables!

Figure 10.2 is an example of an RJ-45 wiring schematic

physical Network diagrams

What if you had to troubleshoot a

network issue in the network diagram

shown in Figure 10.3? Confusing,

right? This is why creating a physical

network diagram is so important

Physical network diagrams contain

each physical device and physical

connection inside your network

Doing this before and during a

net-work deployment is critical to future

network updates and troubleshooting

efforts

Clear and simple physical

dia-grams go a long way (Figure 10.4)

Depending on your network size

and complexity you might need the

FIGurE 10.1

EIA/TIA 568A/B Wiring Schematic.

Image courtesy of howtocable.com

FIGurE 10.2 An RJ-45 Connector Wiring Schematic.

Image courtesy of Wikimedia Commons Photo by Aaron Kasse