Free Practice Questions for CompTIA N10-009 Exam

The first step of troubleshooting is always to identify the problem, which includes verifying the symptoms (incorrect time), asking the user clarifying questions, and checking system logs. Only after confirming the problem can the administrator proceed to form a theory and plan.

A. Plan of action is later.

B. Implement solution comes after testing a theory.

D. Test the theory requires a defined problem first.

References (CompTIA Network+ N10-009):

Domain: Network Troubleshooting — Troubleshooting methodology (Identify → Theory → Test → Plan → Implement → Verify → Document).

A load balancer is the best answer because it sits in the traffic path and distributes client requests across multiple backend servers. Since a load balancer tracks sessions, health checks, connection states, and response timers, incorrect timeout values or overloaded backend systems can cause client sessions to expire before the server responds. When that happens, packets or connections may be dropped, reset, or redirected, creating symptoms that appear as packet loss or failed application communication.

The CompTIA Network+ N10-009 objectives include availability concepts, load balancing, traffic management, and network performance troubleshooting. Load balancers are useful for improving scalability and fault tolerance, but they also introduce another decision point in the traffic path. If persistence, health checks, or timeout settings are misconfigured, application traffic can be interrupted.

An IDS is usually passive and monitors copied traffic, so it is less likely to directly cause packet loss. A CDN generally reduces latency and improves delivery by serving content closer to users. QoS is designed to prioritize important traffic and reduce delay, jitter, and packet loss for sensitive applications such as VoIP. Therefore, the most likely technology to increase packet loss due to timeout is a load balancer.

The correct answer is A. The TX/RX connection is transposed. In fiber optic networking, communication requires proper alignment of the transmit (TX) and receive (RX) strands between devices. If these are reversed (not crossed correctly), the devices cannot properly send and receive signals, resulting in no link light. This is a common issue when working with fiber connections and media converters.

The scenario confirms that cables are tested and functional, and all devices are powered on, which eliminates physical damage or power issues. Fiber cables can still pass basic continuity tests while being incorrectly connected (TX to TX and RX to RX instead of TX to RX), which prevents link establishment.

Option B is incorrect because duplex mismatch (such as half vs. full duplex) typically causes performance issues like collisions and slow throughput, not a complete loss of link light. Option C is ruled out because the cables were tested successfully. Option D refers to errors that occur after a link is established, not a condition preventing link initialization.

According to CompTIA Network+ objectives, proper fiber polarity (TX/RX alignment) is critical for link establishment, making this the most accurate cause.

Asymmetrical routing occurs when packets take different paths to and from the destination, leading to instability in network communication. The use of two different MPLS providers with OSPF can lead to this type of routing issue, especially if the paths aren ' t carefully configured and managed. This can cause unexpected routing behaviors and instability in a dual-WAN setup. (Reference: CompTIA Network+ Study Guide, Chapter on Network Routing)

If the three new employees can communicate with each other’s devices, that strongly suggests their local Layer 2/Layer 3 connectivity is working (same VLAN/subnet, switching is fine, and they have IP addressing that allows local communication). The fact that they cannot access company resources (often on other subnets, servers, or the internet via internal routing) points to a problem with how these new endpoints are being addressed or routed beyond their local segment.

The most likely shared root cause affecting only “new employees” is DHCP scope/pool configuration. If the DHCP pool is exhausted, mis-scoped, or handing out incorrect options (such as an incorrect default gateway, wrong subnet mask, or an address range tied to an isolated VLAN), users could still talk locally but fail to reach resources outside their subnet. Modifying the DHCP server pool (expanding the scope, correcting the scope network, or ensuring the correct options are assigned) would resolve this with minimal changes.

A gateway routing table issue would typically affect many users, not just three new ones. DNS misconfiguration on the router would more commonly cause name-resolution problems, not block all resource access (and wouldn’t be isolated to only new employees). A workstation firewall would not usually prevent access to “company resources” in a way that consistently affects three new devices while still allowing peer connectivity.

An Extended Service Set Identifier (ESSID) allows multiple access points to share the same SSID, enabling seamless roaming for users. This means that users can move between different access points within the same ESSID without losing connection or having to reauthenticate. This provides a better user experience, especially in large environments such as office buildings or campuses.References: CompTIA Network+ study materials. ​

Network Health:

WAN 2 appears to have a lower average latency and loss percentage, which would make it the preferred WAN station for VoIP traffic. VoIP traffic requires low latency and packet loss to ensure good voice quality and reliability. WAN 1 seems to have higher RAM and processor usage, which could also affect the performance of VoIP traffic.

Here ' s the summary of the key metrics for WAN 1 and WAN 2 from the image provided:

WAN 1:

Uplink Speed: 10G

Total Usage: 26.969GB Up / 1.748GB Down

Average Throughput: 353MBps Up / 23.42MBps Down

Loss: 2.51%

Average Latency: 24ms

Jitter: 9.5ms

WAN 2:

Uplink Speed: 1G

Total Usage: 930GB Up / 138GB Down

Average Throughput: 12.21MBps Up / 1.82MBps Down

Loss: 0.01%

Average Latency: 11ms

Jitter: 3.9ms

For VoIP traffic, low latency and jitter are particularly important to ensure voice quality. While WAN 1 has higher bandwidth and throughput, it also has higher latency and jitter compared to WAN 2. However, WAN 2 has much lower loss, lower latency, and lower jitter, which are more favorable for VoIP traffic that is sensitive to delays and variation in packet arrival times.

Given this information, WAN 2 would generally be preferred for VoIP traffic due to its lower latency, lower jitter, and significantly lower loss percentage, despite its lower bandwidth compared to WAN 1. The high bandwidth of WAN 1 may be more suitable for other types of traffic that are less sensitive to latency and jitter, such as bulk data transfers.

Device Monitoring:

the device that is experiencing connectivity issues is the APP Server or Router 1, which has a status of Down. This means that the server is not responding to network requests or sending any data. You may want to check the physical connection, power supply, and configuration of the APP Server to troubleshoot the problem.

A screenshot of a computer AI-generated content may be incorrect.

When configuring a firewall, the first step is identifying which ports, protocols, and services are required for normal business operations. This ensures only legitimate traffic is allowed. After establishing the required rules, a default deny rule is added for security.

B. Deny all rule is important, but it should come after defining required rules.

C. VPN access is a service to configure, but only after determining baseline needs.

D. Outbound traffic policies are part of refinement, not the first consideration.

References (CompTIA Network+ N10-009):

Domain: Network Security — Firewall configuration, rule order, least privilege.

Increasing the MTU (Maximum Transmission Unit) size allows larger frames to be transmitted, reducing overhead and improving throughput — especially for large file transfers like backups.

A. QoS prioritizes traffic but doesn’t reduce backup times directly.

B. SDN is a network management model, not a parameter change.

D. VXLAN encapsulates VLANs, not relevant to backup speeds.

E. TTL is for packet lifetime, not throughput.

References (CompTIA Network+ N10-009):

Domain: Network Infrastructure — MTU, jumbo frames, performance tuning.

When a network administrator installs a new Network Interface Card (NIC) and users are unable to reach the server, one of the common issues is the use of an incorrect cable type. Network cables must match the specifications required by the NIC and the network infrastructure (e.g., Cat5e, Cat6 for Ethernet).

NIC Compatibility: The new NIC might require a specific type of cable to function properly. Using a cable not rated for the NIC ' s required speeds or capabilities can result in connectivity issues.

Cable Standards: Different NICs and network devices might need different cabling standards (straight-through vs. crossover cables, or specific fiber optic types).

Connection Types: Ensuring that the cable connectors are appropriate for the NIC ports (e.g., RJ45 for Ethernet, LC connectors for fiber optics).

Network References:

CompTIA Network+ N10-007 Official Certification Guide: Discusses network cabling standards and NIC specifications.

Cisco Networking Academy: Provides insights into cabling and NIC configurations for optimal network performance.

Network+ Certification All-in-One Exam Guide: Offers comprehensive details on troubleshooting network connectivity issues, including cabling problems.

Comprehensive and Detailed Explanation (aligned to N10-009):

For a log collector server, the primary needed service is Syslog, which typically uses UDP port 514. Other ports may be open for management (e.g., 22 for SSH) or SNMP traps (162) if integrated. However, port 80 (HTTP) should not be open unless required, as it increases attack surface and does not directly serve the log collection purpose. Disabling it hardens the server.

A. 22 (SSH) is needed for secure management.

C. 162 (SNMP trap) may be required for monitoring/log correlation.

D. 514 (Syslog) is essential for log collection.

References (CompTIA Network+ N10-009):

Domain: Network Security — Hardening servers, disabling unnecessary services and ports.

VLAN hopping allows an attacker to send traffic into another VLAN without authorization, often by impersonating a switch and negotiating a trunk link. This lets the attacker traverse into normally inaccessible VLANs.

A. MAC flooding disrupts switch operations but does not cross VLANs.

B. DNS poisoning corrupts name resolution.

D. ARP spoofing reroutes local traffic but doesn’t grant VLAN traversal.

References (CompTIA Network+ N10-009):

Domain: Network Security — VLAN attacks, unauthorized lateral movement.

An out-of-band management solution is the best answer because it provides an alternate administrative path to network equipment when the normal production network path is unavailable. If a switch becomes unresponsive through SSH, the technician needs a separate management method that does not depend on the same in-band network connectivity. Out-of-band management can use a dedicated management network, console server, cellular connection, modem, or management interface to reach devices during outages or configuration failures.

The CompTIA Network+ N10-009 objectives include network operations, device management, availability, and remote access methods. SSH is an in-band management method when accessed over the production network. If routing, VLANs, ACLs, management services, or switch control-plane functions are affected, SSH may fail. Out-of-band access improves administrative redundancy and supports recovery.

A jump host can centralize administrative access, but it still depends on network connectivity to the switch. An administrative GUI may also fail if management access is unavailable. A physical console cable can work locally, but the question specifically asks for remote administrative redundancy. Therefore, an out-of-band management solution is the best answer.

The technician should inspect the client’s firewall configuration. Since only one specific user is unable to access the server while other users can access it successfully, the issue is most likely isolated to that user’s device, account, local configuration, or local security settings. After switch and router logs show no network infrastructure issue, the next logical step is to examine the affected client.

The CompTIA Network+ N10-009 troubleshooting methodology emphasizes identifying the scope of the problem, testing the most likely causes, and isolating whether the issue is client-side, server-side, or network-side. A local firewall could block outbound connections to the server, block a required application, restrict ports, or apply a profile that prevents communication.

Updating network firmware is not an appropriate next step because there is no evidence of a widespread infrastructure problem. Checking the server’s DNS configuration is unlikely because other users can access the same server. Checking the server’s event logs may be useful later, but the scenario points first to the single affected client. Therefore, inspecting the client’s firewall configuration is the best next troubleshooting step.

IPv4 addresses are divided into classes:

Class A: Supports 16,777,214 hosts (large enterprises).

Class B: Supports 65,534 hosts (medium to large networks).

Class C: Supports 254 hosts (small to medium networks).

Class D: Used for multicast, not for assigning IPs to hosts.

Step-by-step Calculation:

The network will have 150 users initially, with a projected growth of 10 users, totaling 160 users.

Each user has two devices, so 160 × 2 = 320 IP addresses needed.

A Class C subnet has 254 usable IPs by default, which is not sufficient.

A Class B subnet can support thousands of hosts, making it the most appropriate option.

Incorrect Options:

A. Class D: Reserved for multicast, not for host assignments.

C. Class A: Overkill for a network of this size.

D. Class C: Cannot support 320 hosts without subnetting, making Class B the best choice.