CompTIA Updated N10-009 Exam Questions and Answers by alistair

A Security Information and Event Management (SIEM) system collects, correlates, and analyzes logs from multiple sources in real-time, providing enhanced visibility across multivendor environments.

Breakdown of Options:

A. SNMP – SNMP is used for network device monitoring, but it lacks real-time correlation across multiple vendors.

B. SIEM – Correct answer. SIEM aggregates, analyzes, and correlates logs from multiple sources, providing real-time visibility.

C. Nmap – Nmap is a network scanning tool used for mapping hosts and detecting open ports but does not provide log correlation.

D. Syslog – Syslog collects logs but does not correlate or analyze them in real-time.

Disabling unused ports prevents unauthorized access and reduces the attack surface by ensuring that no inactive or unmonitored entry points are available for exploitation. Changing default passwords is critical for security because default credentials are widely known and can easily be exploited by attackers. These techniques are fundamental steps in hardening devices against unauthorized access and ensuring network security. References: CompTIA Network+ Exam Objectives and official study guides.

If a switch has port security enabled (such as sticky MAC or a configured allowed MAC), the port will only allow the original NIC’s MAC address. When a new NIC with a different MAC address is installed, the port rejects traffic, preventing network connectivity.

B. BPDU guard protects against rogue switches, not end hosts.

C. Link aggregation applies when bundling multiple uplinks, not a single PC connection.

D. PoE budget applies to powered devices like APs, not PCs.

References (CompTIA Network+ N10-009):

Domain: Network Troubleshooting — Port security, MAC address filtering, switch security features.

The customer can access local resources (a database server), which means local networking is working. However, the inability to reach the internet suggests an issue with the default gateway. If the default gateway is unreachable, packets will not be routed outside the local network.

Breakdown of Options:

A. Incorrect DNS – DNS issues would cause problems resolving domain names, but the user should still be able to access external resources via IP addresses.

B. Unreachable gateway – ✅ Correct answer. If the default gateway is incorrect or unreachable, the device cannot route traffic to the internet.

C. Failed root bridge – STP (Spanning Tree Protocol) failures cause switching issues, but the user can still access local devices, meaning STP is not the problem.

D. Poor upstream routing – Would affect the entire network, not just one user.