CCNA 4, Chapter 8 Exam

Asking the end-user when they first noticed the email problem will provide a clear starting point for troubleshooting. This information will help the technician determine if there were any recent changes or events that could have caused the issue. It will also help in identifying any potential patterns or correlations with other system changes or updates.

The bottom-up troubleshooting method begins by examining cable connections and wiring issues. This approach starts with the physical layer of the network and works its way up to higher layers. By first checking the cables and wiring, any issues or faults in the physical infrastructure can be identified and resolved, which can often solve many network problems. This method is effective in troubleshooting connectivity issues and ensuring that the network is properly connected and functioning at a basic level before moving on to more complex layers.

A network performance baseline should be measured during normal work hours of an organization because it provides a realistic representation of the network's performance under typical usage conditions. This allows for accurate comparisons and analysis of network performance over time. Measuring the baseline during this time also helps identify any potential bottlenecks or issues that may arise during peak usage periods, enabling proactive troubleshooting and optimization.

A protocol analyzer should be used to verify that the setup is correct and that the authentication is indeed encrypted. A protocol analyzer is a tool used to capture, analyze, and interpret network traffic. It can examine the packets exchanged between the client and server during the authentication process and determine if the data is being encrypted using SSL technology. This tool can help the network engineer ensure that the authentication credentials are being protected as intended.

The number 0 represents the most severe level of syslog logging. In syslog, severity levels are used to prioritize and categorize log messages. The severity level 0 is known as "Emergency" and is used for critical system failures that require immediate attention. It indicates the highest level of severity and signifies that the system is unusable or in an unstable state.

The higher than normal framing errors indicate an issue with the physical layer of the network, which is Layer 1 of the OSI model. This layer deals with the physical transmission of data, including the cables, connectors, and signaling. Framing errors occur when there are problems with the synchronization of data between the transmitting and receiving devices. Therefore, the problem is likely occurring at Layer 1.

ARP (Address Resolution Protocol) is used to resolve IPv4 addresses to Layer 2 Ethernet addresses on a host computer. It is a network protocol that allows a device to discover the MAC address of another device on the same network. When a device wants to communicate with another device using its IP address, it uses ARP to obtain the MAC address associated with that IP address. This mapping is stored in the ARP cache, which is used to verify the IPv4 address to Layer 2 Ethernet address mappings on the host computer.

A logical topology diagram typically records the IP address and prefix lengths, routing protocols, and static routes. The IP address and prefix lengths are essential for understanding the network addressing scheme. Routing protocols are recorded to show how devices communicate and exchange routing information. Static routes are included to indicate manually configured paths. The other options, such as device models and manufacturers, cable specifications, and device locations, are typically recorded in a physical topology diagram rather than a logical one.

The network engineer should investigate from the network layer to the application layer because Telnet is an application layer protocol. If the engineer can successfully ping between the two devices, it indicates that the network layer is functioning properly. However, since Telnet is not working, there may be an issue with the higher layers of the OSI model, such as the transport layer, session layer, presentation layer, or application layer. Investigating these layers will help identify the problem with Telnet.

The possible cause of the problem is a corrupted NIC driver. This can lead to the workstation sending excessive frames smaller than 64 bytes and other meaningless frames, resulting in slow performance when connecting to network resources.

The first statement is true because the exhibit shows that IP SLA 99 is configured to send echo requests every 10 seconds. The second statement is true because the exhibit does not provide any information about measuring jitter, so it cannot be determined whether IP SLA 99 is measuring jitter or not.

Network management system tools provide device-level monitoring, configuration, and fault-management. These tools are designed to monitor and manage network devices such as routers, switches, and servers. They allow administrators to monitor the performance and status of these devices, configure them as needed, and troubleshoot any faults or issues that may arise. By providing comprehensive monitoring and management capabilities, network management system tools help ensure the smooth operation of a network and enable quick resolution of any problems that may occur.

NAM (Network Analysis Module) and portable network analyzer are two specialized troubleshooting tools that can monitor the amount of traffic that passes through a switch. NAM is a module that can be installed in a switch to provide detailed network traffic analysis and monitoring capabilities. A portable network analyzer, on the other hand, is a standalone device that can be connected to a switch to capture and analyze network traffic. Both tools are useful in troubleshooting network issues and monitoring network performance.

The problem is that the ASBR does not have OSPF neighbor. This means that the ASBR is not forming OSPF adjacencies with the other routers in the organization. As a result, the other routers are not receiving the default route information from the ASBR, and therefore, the users throughout the organization cannot access the Internet.

In the process of gathering symptoms, the network engineer determines if the problem is at the core, distribution, or access layer of the network by narrowing the scope. This step involves analyzing the documented symptoms and gathered information to identify the specific area or layer where the issue might be occurring. By narrowing down the scope, the engineer can focus their troubleshooting efforts on the relevant layer, which helps in resolving the problem more efficiently.

Establishing a network baseline serves the purpose of creating a point of reference for future network evaluations. This means that it allows network administrators to have a benchmark or standard against which they can compare the performance and behavior of the network over time. By establishing a baseline, any deviations or abnormalities in network performance can be easily identified and addressed. This helps in troubleshooting network issues, optimizing performance, and planning for future network upgrades or changes.

The team should follow change-control procedures while implementing the solution to avoid interfering with other processes and infrastructure. Change-control procedures ensure that any changes made to the network are properly planned, tested, and documented. This helps to minimize the risk of unintended consequences or disruptions to other systems. By following change-control procedures, the team can ensure that the proposed solution is implemented in a controlled and organized manner, reducing the chances of interference with critical network infrastructure components.

The issue could be that static NAT has not been configured properly or at all. Static NAT is a method used to translate the private IP address of an internal server to a public IP address that can be accessed over the internet. If static NAT is not configured properly or not configured at all, the internal server's private IP address will not be translated to a public IP address, making it inaccessible to external internet users.

The ipconfig command will provide the IP address and DNS configurations on the PCs. The nslookup command will allow the technician to verify the DNS configuration and check if the PCs can resolve domain names. The ping command will help the technician verify connectivity to the local router by sending ICMP echo requests and checking for responses.

The PC has a missing or incorrect default gateway, which is causing it to have trouble accessing the Internet. The default gateway is responsible for routing network traffic between different networks, such as the local network and the Internet. If the PC does not have a default gateway configured, or if the configured default gateway is incorrect, it will not be able to properly route its network traffic to the Internet. This is why the PC is able to print to a local printer and ping other computers on the same network, but is unable to access the Internet.

The correct answer is transport. In this scenario, the helpdesk technician is able to access the website using a specific port number (port 90) but not the default port number (port 80). This indicates that there may be an issue with the transport layer of the TCP/IP model. The transport layer is responsible for establishing connections and ensuring reliable data transfer between devices. By accessing the website with a different port number, the technician is troubleshooting the issue at the transport layer.

The cause of the problem is that the serial interface encapsulation is configured incorrectly. This means that the configuration of the interface that connects PC0 to the network is not set up properly, causing PC0 to be unable to visit the web server.

In a top-down approach to troubleshooting, the network administrator would start at the highest layer of the OSI model, which is the application layer. However, since the issue is related to the network not appearing in other routers, the network layer would be the logical starting point for troubleshooting. This layer is responsible for routing and addressing, so it is likely that there is a problem with the network configuration or routing protocols that is causing the network not to be visible to other routers.

The technician should check the status of the departmental workgroup switch in the wiring closet as the first step in troubleshooting the issue. Since multiple machines in the same department are experiencing the same problem and cannot ping each other, it suggests that the issue may be related to the workgroup switch that connects those machines to the network. Checking the status of the switch will help determine if it is functioning properly and if there are any configuration or connectivity issues that need to be addressed.

At stage 3 of the general troubleshooting process, the action that occurs is to correct the problem. This means that after identifying the problem and narrowing down the scope of the issue, the next step is to take the necessary actions to resolve the problem and fix any errors or malfunctions. This may involve implementing solutions, making adjustments, or repairing any faulty components or systems in order to restore normal functionality.

After determining ownership and narrowing the scope, the next step in the network troubleshooting process would be gathering symptoms from suspect devices. This step involves collecting information and data from the devices that are suspected to be causing the issue. By gathering symptoms from these devices, network administrators can analyze the data and identify any patterns or anomalies that may help in troubleshooting and resolving the network problem. This step is crucial in the layered troubleshooting approach as it focuses on specific devices and their symptoms to further investigate and diagnose the issue.