CompTIA Linux+ XK0-006 (V8) Practice Question

The correct answer is to use iptables -L INPUT -v -n. Given the scenario, the web service is running and accessible locally, and basic network connectivity is confirmed via ping. This strongly suggests that a firewall is blocking incoming traffic to port 80 from external sources. The iptables -L INPUT -v -n command is the most direct way to investigate this by listing the rules for the INPUT chain in a verbose and numeric format, which would quickly show if a rule is dropping or rejecting TCP packets destined for port 80.

• systemctl restart httpd is incorrect because the service is already confirmed to be running and working locally. Restarting it is unlikely to solve a network access problem.
• route -n is incorrect because successful pings indicate that layer 3 routing between the client and server is working correctly.
• getenforce is incorrect because while SELinux could potentially cause such an issue, the symptoms are a classic example of a network firewall misconfiguration. The firewall is the first and most probable component to check.