Rangkuman CCNA Discovery 2 - Chapter 2

HELP DESK

Many business operations depend on a connection to the local network and the Internet. Therefore, network troubleshooting is a top priority for the business.

ISPs provide internet connections for business, and they give their customer support for problems that occur with Internet connectivity. This support usually includes assistance with customer equipment problems. ISP support is typically provided through an ISP help desk. Is it a problem connecting to the Internet or receive email, help desk ISP is usually the first place users or businesses turn to for help.

ISP help desk technicians have the knowledge and experience to fix the problem and get the user connected. ISP help desk technician to provide solutions to customer issues with the goal of network optimization and customer retention.

A good help desk team to ensure that problems are resolved quickly and to the satisfaction of the customer. Providing Internet services is a very competitive business, and poor service can lead to loss of customers to the ISP ISPs compete.

At ISP, there are usually three levels of customer support:

Level 1 is for direct support is handled by a junior-level help desk technician.

Level 2 handle increased calls for more experienced telephone support.

Level 3 is for calls that can not be resolved by phone support and require on-site visits by technicians.

In addition to ISP, different types of media to large businesses employ help desk or customer support team. Title assigned to the technician may differ from those described here, although the hierarchy of three levels is the most common structure. Depending on the size of the organization, help desk may consist of one person doing all three levels of support, or could be comprehensive call center with complex facilities conquest calls and escalation rules. Some ISPs and businesses contract out their help desk functions to a third-party company call center, which provides services from Level 1 and Level 2 technicians.

When the user initially contacted the help desk to resolve the problem, call or message is usually directed to Level 1 support technician. Level 1 support is usually an entry-level position that provides junior technicians with valuable experience. Many customers issued resolved by Level 1 support technician.

Problems can not be solved sent to Level 2 support, which typically have fewer available agents. Tasks and responsibilities of Level 2 technician that is similar to the Level 1 technician, but they are at a higher skill level. These agents are expected to solve problems that are more challenging and require more knowledge.

Many of the larger service providers have expanded their business to include managed service or on-site support of customer networks. Organizations that provide managed services are sometimes referred to as Managed Service Providers (MSP). Managed services can be provided by the ISP, telecom service providers, or any other type of computer support and networking organization. When an ISP that provides managed services, often requiring a technician to visit the customer site for the purpose of installation and support. This type of service is a Level 3 support.

Level 3 support is generally in accordance with the Service Level Agreement (SLA). SLA resemble an insurance policy, as it provides coverage or services if there is a computer or a network problem.

Help desk technicians may be required to provide telephone support, email support, web-based support, online chat support, and possibly on-site support. They are often the first point of contact for customers frustrated and anxious. Until the problem is solved, help desk technician can continue to get calls and correspondence asking for status updates and estimated time to resolve the problem.

Incident management procedures to be followed every time a help desk technician receives a call and begin to address the problem. Incident management including open tickets and follow the interference problem-solving strategies. Using troubleshooting techniques including troubleshooting flowcharts, addressing questions in a template format, and maintain appropriate procedures increased ticket.

A script is used by help desk help desk technicians to collect information and cover the important facts about customer events.

In addition to technical skills, help desk technician should be able to greet customers happy and to be professional and polite throughout the call.

Customer service and interpersonal skills are very important when handling difficult clients and incidents. Help desk technician should know how to relieve stress and respond to customer rude customer.

Ticket trouble opening and logging information on the ticket is very important to help desk operations. When there are a lot of calls regarding a problem or symptoms, it is helpful to have information on how the issue was resolved in the past. It is also important to communicate to the customer what is being done to solve the problem. Good information on open trouble tickets help the communication status accurately, both with customers and other ISP personnel.

While many problems can be handled remotely, some problems require on-site visits to the customer site to install and troubleshoot equipment. When a technician to go anywhere, it is important to represent them in a professional organization. A professional knows how to make customers feel comfortable and confident in the skills of technicians.

On my first visit to the customer site, it is important for technicians to make a good impression. Personal care and how technicians dress is the first thing customers notice. If the technician makes a bad first impression, it may be difficult to change that impression and gain the trust of customers. Many employers provide uniforms or have a dress code for their on-site technicians.

The language and attitude of the technicians also reflects the organization representing technicians. when talking to the customer, the technician should be polite and respectful, and answer all customer questions. If the technician does not know the answers to customer questions or if additional information is required, the technician must write to customer inquiries and follow up as soon as possible.

When network connectivity problems reported to the help desk, many methods are available to diagnose the problem. One common method is to solve the problem by using a layered approach. A layered approach requires that the network engineers become familiar with the various functions that occur as a message is created, presented, and interpreted by the network devices and hosts on the network.

Transferring data over a network is best imagined with seven layers of the Open Systems Interconnection, commonly referred to as the OSI model. The OSI model breaks network communication into multiple processes. Each process is a small part of the larger task.

The seven layers of the OSI model is divided into two sections: the top layer and bottom layer.

The upper layer of the term is sometimes used to refer to any layer above the Transport layer of the OSI model. The top layer deals with the application functionality and are generally only implemented in software. Highest layer, the application layer, closest to the end user.

The bottom layer term is sometimes used to refer to any layer below the Session layer. The combined functions of the lower layers handles data transport. Physical layer and Data Link layers are implemented in hardware and software. The physical layer is closest to the physical network media, or network cabling. The physical layer actually put the information to the media.

End stations, such as clients and servers, usually work with all seven layers. Network devices are only concerned with the bottom layer. Hub works at Layer 1, moved at Layers 1, 2 and routers at Layers 1, 2 and 3, and firewalls at Layers 1, 2, 3, and 4.

When using the OSI model as a framework for troubleshooting, it is important to understand the work performed on each layer, and what information is available to the network device or software programs perform these functions. For example, many processes have to happen because email to successfully travel from the client to the server. The OSI model divides the task of sending and receiving emails becomes smaller, the different measures corresponding to seven layers.

Step 1: The top layer is made of data.

When a user sends an email message, the alphanumeric characters in the message are converted into data that can travel across the network. Layers 7, 6, and 5 are responsible for ensuring that the message is placed in a format that can be understood by the application running on the host destination. This process is called encoding. The top layer then sends a coded message to the lower layers for transport across the network. Transporting mail to the correct server depending on the configuration information provided by the user. Problems that occur at the application layer that is often associated with an error in the configuration of the software program users.

Step 2: Layer 4 packet data for end-to-end transport.

The data consists of email messages in containers for transport network at Layer 4. Layer 4 break messages into smaller segments. A title placed on each segment which shows TCP or UDP port number corresponding to the correct application of the application layer. The functions in the transport layer indicates the type of service delivery. Email using TCP segments, so sending packets acknowledged by the destination. Layer 4 functions are implemented in software running on the source and destination hosts. However, because firewalls often use TCP and UDP port numbers to filter traffic, a problem that occurs at Layer 4 can be caused by a list of appropriate firewall filter set.

Step 3: Layer 3 adds the network IP address information.

Email data received from the transport layer entered into a package that contains a header with source and destination IP address of the network. The router uses the destination address to redirect packets across the network along the right path. One IP address is configured on the source of information or the destination system can cause Layer 3 problems to occur. Because routers also use IP address information, the router configuration errors can cause problems at this layer.

Step 4: Layer 2 adds the data link layer header and trailer.

Every network device in the path from source to destination, including the sending host, encapsulates the packet into a frame. Frame contains the physical address of the device that is connected directly to the next network link. Every device in the network path requires framing chosen so that it can connect to the next device. Switches and network interface cards (NICs) using the information in the frame to convey the message to the correct destination. NIC driver is not correct, interface cards, and hardware problems with the Layer 2 switch can cause the problem to occur.

Step 5: Layer 1 converts data to bits for transmission.

Frame is converted into a pattern of 1s and 0s (bits) for transmission on the medium. A clock function allows the device to distinguish these bits as they travel across the medium. Media can change along the path between the source and destination. For example, an email message can start in one Ethernet LAN, across a campus backbone fiber, and cross serial WAN link to another until it reaches the destination Ethernet LAN remotely. Layer 1 problem can be caused by a loose or incorrect wiring, faulty interface card, or power failures.

On the receiving host, the process described in steps 1 through 5 is reversed, with the message the way back to the appropriate application layer.

As a theoretical model, the OSI model defines the protocols, hardware, and other specifications that operate in seven layers.

The OSI model also provides a systematic basis for network troubleshooting. In each scenario troubleshooting, basic troubleshooting procedures include the following steps:

1. Defining the problem.

2. Isolating the cause of the problem.

3. Solve the problem.

Identify and prioritize alternative solutions.

Select one of the alternatives as a solution.

Implement the solution.

Evaluate the solution.

If the solution does not address the identified problem, undo the change and move on to the next possible solution. Go through the steps until the solution works.

Besides basic troubleshooting procedures, the OSI model can be used as a guide for troubleshooting. Using a layered model, there are three different problem-solving approaches that a technician can use to isolate the problem:

Bottom-Up - bottom-up approach starts with the physical components of the network and works its way up layers of the OSI model. Bottom-up approach to problem solving is an effective and efficient for suspected physical problems.

Top-Down - top-down approach starts with the user's application and work your way down the layers of the OSI model. This approach begins with the assumption that the problem is with the application and not the network infrastructure.

Divide-and-Conquer - The divide-and-conquer approach more commonly used by experienced network engineers. Technicians make an educated guess targeting the problem layer, and then based on the results of observations, move up or down the OSI layers.

Using the OSI model as a guide, help desk technician can query customers to help define the problem and isolate the cause.

Help desk technicians usually have a predefined list or script to follow when troubleshooting a problem. Often the script take a bottom-up approach to problem solving. This is due to physical problems are usually the most simple to diagnose and repair, and the bottom-up approach starts with the Physical Layer.

Layer 1 Troubleshooting

Technicians began with Layer 1 first issue. Remember, Layer 1 relate to the physical connectivity of network devices. Layer 1 problem often involves wiring and electricity, and is the reason for many help desk calls. Some problems are more common Layer 1 includes:

Power off the device

Power device is disconnected

Loose network cable connection

One type of cable

Damage to the cable network

Damaged wireless access point

One wireless settings such as SSID

To solve the problem at Layer 1, first check that all devices have the proper power supply, and that the device is turned on. if the problem is with the wireless, make sure the wireless access point operation and that the wireless settings are configured correctly.

When a little troubleshooting a problem, the technician must notify the caller through each step, what to look for, and what to do if an error is found. If it is determined that all Layer 1 issue has been addressed, it is time to go on, the OSI model to Layer 2.

Troubleshooting Layer 2

Network switches and host NIC perform Layer 2 functions. Layer 2 problems can be caused by faulty equipment, incorrect device drivers, or switch is not properly configured. When a little troubleshooting a problem, it may be difficult to isolate a Layer 2 problem.

A technician in place to check whether the NIC is installed and working properly. Reseating the NIC, or replace suspected faulty NIC with a known good NIC, helping to isolate the problem. The same process can be done with a network switch.

Layer 3 Problems

At Layer 3, the technician needs to investigate the logical addressing used in the network. If the network uses IP addressing, the technician verifies that the device has the correct settings, such as:

-Assigned IP address in the network

-True subnet mask

Right-default gateway

-Other settings are required, such as DHCP or DNS

At Layer 3, several utilities to assist with the troubleshooting process. Three of the command line tools are the most common:

-Ipconfig: Shows the IP settings on the computer

-Ping: Tests the basic network connectivity

-Tracert: Determine if the routing path between the source and destination are available

Many network problems can usually be solved using Layer 1, 2, and 3 problem solving techniques.

Layer 4 Troubleshooting

If Layers 1 through 3 all appear to be operating normally and technicians can successfully ping the IP address of the remote server, it is time to examine higher layers. For example, if the network firewall is used throughout the flow, it is important to check that the application TCP or UDP port is open and no filter list to block traffic to the port.

Layer 5 to 7

The technician should also check the application configuration. For example, when troubleshooting an email issue, ensure that the application is configured with the correct shipping and receiving email server information. It is also necessary to ensure that the domain name resolution function as expected.

For remote technician, higher layers can be examined using tools other network utilities, such as packet sniffer to see the traffic as it crosses the network. A network applications, such as Telnet, can also be used to view the configuration.

The number and type of calls received by the help desk can vary widely. Some of the most common calls include problems with email, connectivity host configuration

Common causes of many problems email was using the wrong lift, IMAP, or SMTP server name. It is best to check with your email administrator to confirm the exact name of the POP or IMAP server and the SMTP server. In some cases, the same name servers for both POP / IMAP and SMTP is used. Also, make sure that the username and password are correct. Since passwords are usually not shown, it is a good idea to carefully put it back.

When troubleshooting problems with the phone, it is important to step customers through the configuration parameters carefully. Many customers are not familiar with the term and setting the various configuration parameters. If possible, connect the device to customers through remote management software. This allows technicians to perform the necessary steps for the customer.

Host Configuration Problems

Common problems that can prevent connectivity to the Internet or other network resources are improperly configured host addressing information. This can include the wrong IP address, subnet mask, or default gateway.

In environments where the IP addressing information manually configured, it is possible that the IP configuration is entered incorrectly. In an environment where the occupants set to dynamically receive an IP address from the server tasks, such as DHCP server, the server may fail or become unreachable due to network problems.

If a host is configured to receive dynamic addresses, and one assignment server is not available or not affordable, link-local address will be automatically assigned to the local host by the operating system. IPv4 address 169.254.0.1 in the address block to 169,254,255,254 (169.254.0.0 / 16) defined as the link-local address. A link-local process will randomly select an IP address in the range 169.254.0.0/16. But what prevents the two hosts of the random selection of the same IP address?

After the process of selecting a link-local IP address, it sends an ARP request with the IP to the network to see if there are other devices that use that address. If there is no response, the IP address assigned to the device, if the IP address is selected, and repeated ARP requests. Microsoft refers to the link-local address as Automatic Private IP Addressing (APIPA).

If multiple hosts on the same network have the address link-local, client / server and peer-to-peer applications between that residents will work fine. However, because link-local address is in a Class B address space private communication, outside of the local network is not possible.

When troubleshooting both manually and dynamically configured hosts, use the host command ipconfig / all to verify that the host is using the appropriate IP configuration.

Customer Connectivity Problems

Connectivity problems are more common with new customers trying to connect for the first time. However, sometimes there are customers are experiencing connectivity problems. First time customers may have problems with installing the hardware and software configuration settings. Existing customers experiencing connectivity problems when they can not open a webpage or connect to the instant messaging or email.

There are many reasons why customers have no connectivity, including the following:

-Failure to pay for services

-Hardware failure

Physical-layer failure

-One application settings

-Missing plug-in application

-Missing apps

In many cases, the problem is a faulty cable, or a cable plugged into the wrong port. This type of problem can be solved by checking the cable connections or replace cable.

Other problems, such as a software problem, it may be more difficult to detect. One example is the stack TCP / IP is loaded incorrectly. The stack TCP / IP can be tested and verified using the loopback address. Loopback is a special address, the IPv4 address 127.0.0.1 booked, residents who used to drive traffic to themselves. Loopback address creates shortcut method for TCP / IP applications and services running on the same device to communicate.

You can ping the loopback address to test the TCP / IP configuration on the local host. If you are unable to get a response when pinging the loopback address, suspect TCP / IP stack improperly configured or installed.

Address 127.0.0.0 to 127 255 255 255 are reserved for testing purposes. Each address in this block will be repeated in the local host. There are no addresses in this block should ever appear on any network. Despite the fact that the range 127.0.0.0 / 8 are reserved throughout the network, the address is usually used for testing only loopback address is 127.0.0.1.

When a Level 1 help desk technician receives a call, there is a process to follow to gather information. There is also a special system to store and retrieve relevant information. It is very important to gather information correctly in case the call should be increased to a Layer 2 or require on-site visits.

Meeting information and record the process started as soon as the technician answered the phone. When customers identify who they are, technician access to relevant customer information. Typically, database applications used to manage customer information.

The information was transferred to a disturbance ticket, or incident reports. This document could be a piece of paper in a paper filing system or an electronic tracking system that is designed to follow the problem-solving process from start to finish. Everyone who worked on the matter is expected to record what was done at the ticket interference. When the call is in place necessary, disruption ticket information can be converted into a work order on-site technicians can take to the customer site.

When a problem is solved, the solution was documented in the customer work order or trouble ticket, and within-document knowledge base for future reference.

Sometimes, the technician level 1help table can receive calls that can not be resolved quickly. In this case, the technician is responsible for passing the call to Level 2 technicians are better qualified to resolve the issue. Passing the call to a higher level technicians known as the process of increasing the call.

Both Level 1 and 2 help desk technician level trying to solve customer problems using the phone, web tools, and remote desktop sharing applications possible.

If the help desk techs can not fix the problem remotely, it is often necessary to send a technician on-site Level 3 to the customer premise location. It is the job of the technician in place to visit for a customer premise equipment to physically work on the problem. Help desk technician can make an appointment with the customer to technician on site to carry out repairs, or perhaps responsibility technicians in place to set up an appointment.

To really solve the problem, technicians at the place a trouble ticket to see what was previously done. This review gives engineers some background information and a logical starting point. It also helps the technician to decide which tools and equipment to carry, rather than having to leave the customer site to get supplies.

On-site technicians usually work on the network at a customer site, although there are some instances where the technician was not able to make the necessary repairs and had to bring the damaged equipment back to the site the ISP for additional troubleshooting.

There are four steps in place before beginning technicians perform troubleshooting or repair at the customer site:

Step 1. Provide proper identification to the customer.

Step 2. Review the work order ticket or interference with the customer to verify that the information is correct.

Step 3. Communicate the status of any problems identified and action is expected to take a technician at a customer site that day.

Step 4. Getting permission from the customer to start the work.

Technicians should verify all items on the ticket interference. Once technicians become familiar with all the issues, the work can begin. Technician is responsible for checking all devices and network settings, and run each utility is required. Technicians may also have to swap the suspected faulty hardware with known good hardware to determine if there is a hardware problem.

There are four steps in place before beginning technicians perform troubleshooting or repair at the customer site:

Step 1. Provide proper identification to the customer.

Step 2. Review the work order ticket or interference with the customer to verify that the information is correct.

Step 3. Communicate the status of any problems identified and action is expected to take a technician at a customer site that day.

Step 4. Getting permission from the customer to start the work.

When doing tasks solving customer sites, especially when installing new or replacing existing equipment, it is important to minimize the risk of injury by following safety practices are good. Many employers offer safety training as part of their employee services.

-Appliances

Use the ladder to reach high locations to install network cables and to install or troubleshoot wireless access in places that are hard to reach.

-High or Hazardous Locations

Sometimes network equipment and cables are located in the high and dangerous places, such as on the side of the building, on the roof, or in the internal structures such as the elevator shaft, which is not accessible by stairs. The work done on the location of this type should be done very carefully.

-Electrical

If there is a risk of damaging or come in contact with power lines when handling hardware, consult with electricity from customers about the steps that can be taken to reduce the risk of electric shock

-Awkward Spaces

Network equipment is often located in a cramped and awkward. Ensure that the work area is good tersinari and ventilated. Determine the best way to lift, install, and remove equipment to minimize the risk.

-Heavy Equipment

Network devices can be bulky and heavy. Plan to have the correct equipment and trained personnel when equipment needs to be installed or removed at the customer site.

Once the technician to make configuration changes or install new equipment, the technician should observe the results to ensure proper operation. Once completed, the technician communicates the nature of the problems identified to the customer, what solution is applied, and any follow-up procedures. Before the problem can be considered fully resolved, the technician must obtain a receipt from the customer. Technicians can then close the ticket and document solutions disorders.

Copies of the documentation was left with customer.Technician recording solutions, and customer acceptance is marked on the ticket interference. For future reference, the technician also record problems and solutions in help desk documentation and FAQ.

In some cases, a technician on-site to uncover problems that require network upgrades or reconfiguration of network devices. When this happens, it may be outside the scope of the original ticket disorders. These issues are usually communicated to both the customer and the ISP network personnel for further action.