CompTIA XK0-006 Dumps Questions Answers

This issue is a classic example of post-reboot connectivity troubleshooting, which falls under the Troubleshooting domain of CompTIA Linux+ V8. The administrator has correctly gathered evidence using multiple diagnostic tools, allowing the root cause to be identified through correlation.

The ss -lnt output confirms that the SSH daemon is running and listening on TCP port 22. This eliminates the possibility that the SSH service failed to start after reboot. Additionally, the uptime output shows a very low load average, indicating that system performance is not a limiting factor. The successful ping test confirms that the server is reachable at the network layer and that DNS resolution and basic connectivity are functioning correctly.

The critical clue comes from the firewall configuration. The output of firewall-cmd --list-all shows that only specific services are allowed through the firewall, such as https, dns, and cockpit. The SSH service is notably absent. On systems using firewalld, services must be explicitly allowed, even if the daemon itself is running and listening on the correct port.

As a result, incoming SSH connection attempts are being blocked by the firewall, preventing users from accessing the server remotely after reboot. This aligns precisely with option B.

The other options are incorrect. DNS is functioning, as shown by successful ping responses. System load is low and not contributing to the issue. There is no indication that users are attempting to access the web server using an incorrect protocol.

Linux+ V8 documentation emphasizes that administrators must verify both service status and firewall rules when diagnosing access issues. In this case, allowing SSH with a command such as firewall-cmd --add-service=ssh --permanent followed by a reload would resolve the problem.

Container orchestration concepts are part of the Automation and Orchestration domain in Linux+ V8. In Kubernetes, workloads run inside Pods, but Pods are not directly accessible from outside the cluster.

To expose an application externally, a Service resource must be created. Services provide a stable network endpoint and can be configured as NodePort, LoadBalancer, or ClusterIP. Public exposure is typically achieved using NodePort or LoadBalancer types.

Option C, Service, is correct. Deployments manage Pods, but they do not handle networking exposure. Pods represent running containers but lack external accessibility by default. “Network” is not a valid Kubernetes resource type.

Linux+ V8 documentation highlights Services as the mechanism for exposing containerized applications. Therefore, the correct answer is C.

Hardware inventory and system information gathering are core responsibilities in Linux system management and are explicitly covered in CompTIA Linux+ V8 objectives. Among the listed commands, dmidecode is the most comprehensive tool for retrieving detailed hardware inventory information.

The dmidecode command reads data directly from the system’s DMI (Desktop Management Interface) / SMBIOS tables, which are provided by the system firmware (BIOS or UEFI). It reports detailed information about system hardware components, including motherboard details, BIOS version, system manufacturer, CPU sockets, memory slots, installed RAM modules, serial numbers, and asset tags. This makes it the preferred tool when a full hardware inventory is required.

The other options provide only partial or specific information. lsmod lists currently loaded kernel modules and does not provide physical hardware inventory. dmesg displays kernel ring buffer messages, which may include hardware detection logs but are not structured or complete inventory data. lscpu reports CPU architecture and processor details only, not the entire system hardware.

Linux+ V8 documentation highlights dmidecode as the authoritative utility for system hardware discovery and inventory auditing. It is commonly used in enterprise environments for documentation, troubleshooting, capacity planning, and compliance reporting.

Because it provides the most complete and authoritative hardware information available from the system firmware, the correct answer is A. dmidecode.