ccna dis2 - chapter 2 help desk_ppt [compatibility mode]

8/3/2019 CCNA Dis2 - Chapter 2 Help Desk_ppt [Compatibility Mode]

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Chapter 2 Help Desk

CCNA Discovery 4.0


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Hc vin cng ngh thng tin Bach Khoa - Website: www.bkacad.com

Objectives

Describle the various roles of help desk and installationtechnicians.

Describle the seven layers of the OSI model and how theOSI model is used in troubleshooting network issues.

Identify common tools and diagnostic procedures of helpdesk technicians. Describle on-site procedures to resolve issues.
http://www.bkacad.com/http://www.bkacad.com/


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Help Desk Technicians

ISP Help Desk Organization ISP help desk technicians have the knowledge and experience to fix problems

and get users connected.

ISP help desk technicians provide solutions to customers' problems with thegoal of network optimization and customer retention.

Whether the problem is connecting to the Internet or getting email, the ISPhelp desk is usually the first place a user or business turns to for help. A good help desk team ensures that problems are resolved quickly and to the

customer's satisfaction.


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ISP Help Desk Organization Level 1 is for immediate support handled by junior-level help desk technicians. Level 2 handles calls that are escalated to more experienced telephone

support.

Level 3 is for calls that cannot be resolved by phone support and require a visit

by an on-site technician.


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Roles of ISP technicians


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Interacting with Customers Help desk technicians may be required to provide phone support, email

support, web-based support, online chat support, and possibly onsite support.

The help desk technician must be able to keep focused in an environment withfrequent interruptions and perform multiple tasks efficiently and accurately.

The help desk technician has to have excellent interpersonal skills andeffective communication skills, both oral and written. It is also important for the help desk technician to be able to handle customer

issues with speed, efficiency, and professionalism.

Basic incident management procedures should be followed every time a helpdesk technician receives a call and begins troubleshooting issues.

Problem-solving techniques include using troubleshooting flowcharts,addressing questions in a template format, and maintaining proper ticket

escalation procedures.


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Interacting with Customers In addition to technical ability, help desk technicians need other skills to

be successful.

Some of the skills


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OSI Model

Using the OSI Model When a network connectivity problem is reported to the help desk, there are

many methods available to diagnose the problem.

One common method is to troubleshoot the problem using a layered approach. Using a layered approach requires that the network technician be familiar with

the various functions that occur as messages are created, delivered, andinterpreted by the network devices and hosts on the network.

It is best visualized using the seven layers of the Open SystemsInterconnection (OSI) model

The OSI model breaks network communications down into multiple processes.Each process is a small part of the larger task.

In a similar manner, the OSI model can be used as a reference whentroubleshooting to identify and resolve network problems.

Detail: Chapter 2_2.2.1


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OSI Model

Using the OSI Model


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OSI Model

OSI Model Protocols and Technologies Step 1: Upper Layers creat the data


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OSI Model

OSI Model Protocols and Technologies Step 2: Layer 4 packages the data for end-to-end transport. Step 3: Layer 3 adds the network IP address information.


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OSI Model

OSI Model Protocols and Technologies Step 4: Layer 2 adds the data link layer header and trailer. Step 5: Layer 1 converts the data to bits for transmission.

Activity 2.2.2


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OSI Model

Troubleshooting Using the OSI ModelThe basic problem-solving procedure includes the following:

1. Define the problem.2. Isolate the cause of the problem.3. Solve the problem:

Identify and prioritize alternative solutions Select one alternative as the solution

Implement the solution

Evaluate the solution


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OSI Model

Troubleshooting Using the OSI Model Layer 1 Troubleshooting, problems include the following:

Device power off

Device power unplugged

Loose network cable connection

Incorrect cable type Faulty network cable


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OSI Model

Troubleshooting Using the OSI Model Layer 2 Troubleshooting

Network switches and host NICs perform Layer 2 functions.

Layer 2 problems can be caused by faulty equipment, incorrect devicedrivers, or an improperly configured switch.

Layer 3 Troubleshooting IP address within the assigned network

Correct subnet mask

Correct default gateway

Other settings as required, such as DHCP or DNS

Command:

ipconfig- Shows IP settings on the computer

ping- Tests basic network connectivity

traceroute- Determines if the routing path between the source anddestination is available


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OSI Model

Troubleshooting Using the OSI Model


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OSI Model

Troubleshooting Using the OSI Model Layer 4 Troubleshooting

Layers 1 through 3 all appear to be operating normally and the techniciancan successfully ping the IP address of the remote server

Test Layer 4, if a network firewall is used along the path, it is important tocheck that the application TCP or UDP port is opened and no filter lists areblocking traffic to that port.

Layer 5 through layer 7 Troubleshooting The technician should also check the application configuration.

For example, if troubleshooting an email issue, ensure that the applicationis configured with correct sending and receiving email server information. It

is also necessary to ensure that domain name resolution is occurring For remote technicians, higher layer issues can be checked by using other

network utility tools, such as a packet sniffer, to view traffic as it crossesthe network.


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OSI Model

Troubleshooting Using the OSI Model


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ISP Troubleshooting

Help Desk Troubleshooting Scenarios The number and types of calls received by the help desk can vary extensively. Some of the most common calls include email and connectivity issues. Email Issues:

Can receive but not send

Can send but not receive Cannot send or receive

Nobody can reply to messages

A very common cause of many email problems is using the wrong POP, IMAPor SMTP server names

Another problem that can affect the function of applications is a failure of DNSto correctly resolve server names.

Command: ping or nslookup.


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ISP Troubleshooting

Help Desk Troubleshooting Scenarios Customer Connectivity Issues

Billing account issues

Hardware failure

Physical layer failure

Application settings Application plug-in missing

Missing applications


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ISP Troubleshooting

Creating and Using Help Desk Records1. Level 1 help desk technician receives a call2. Call has to be escalated to Layer 2, or even need an on-site visit.3. The information gathering and recording process starts as soon as the

technician answers the phone.

4. When the customer identifies who they are, the technician accesses therelevant customer information.5. The information is transferred to a trouble ticket, or incident report.6. When a problem is resolved, the solution is documented in the customer work

order or trouble ticket, and in a knowledge-base document for future reference

7. Level 1 and Level 2 help desk technicians attempt to solve customer problems

using the telephone, web tools, and possibly even remote desktop sharingapplications.


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ISP Troubleshooting

Creating and Using Help Desk Records


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ISP Troubleshooting

Creating and Using Help Desk Records If the help desk technicians are not able to remotely fix the problem, it is often

necessary to dispatch a mobile on-site technician to the customer premiselocation.

The help desk technician can make an appointment with the customer for theon-site technician to perform the repairs, or it may be the responsibility of the

on-site technician to arrange the appointment.


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ISP Troubleshooting

Customer Site ProceduresThere are four steps an on-site technician should perform before beginning any

troubleshooting or repair at the customer site:

Provide proper identification to the customer. Review the trouble ticket or work order with the customer to verify that the

information is correc

Communicate the current status of any identified problems or issues, as wellas the actions the technician expects to take at the customer site that day.

Obtain permission from the customer to begin the work.The technician must verify all items on the trouble ticket

Once the technician is familiar with all issues, the work can begin.

The technician checks all device and network settings, and runs any necessaryutilities.


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ISP Troubleshooting

Customer Site Procedures When finished, the technician communicates the nature of the identified

problem to the customer, what solution was applied, and any follow-upprocedures.

Before the problem can be considered fully resolved, the technician mustobtain the customer's acceptance.

The technician can then close the trouble ticket and document the solution.


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Summary


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ccna dis2 - chapter 2 help desk_ppt [compatibility mode]

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