A technician wants to configure a Unix server as a gateway firewall. The technician has implemented the proper ACLs and port address translation policies, but network traffic is not passing from the L

Note - the provided answer is A (DenyHouse), which is not a recognized Linux networking component for enabling packet routing. The technically correct answer for this scenario is ip_forward (choice C): setting net.ipv4.ip_forward=1 via sysctl instructs the Linux kernel to forward packets between interfaces rather than discarding them. ACLs and PAT rules alone are insufficient - the kernel must be explicitly told to route packets between the LAN and WAN interfaces.

Squid is a web proxy and caching service that operates at the application layer; it does not enable kernel-level packet forwarding between network interfaces.

ip_forward is actually the correct Linux kernel parameter for enabling inter-interface packet routing on a gateway firewall, making it the technically accurate answer for this scenario.

/etc/services maps service names to port numbers for reference by applications and has no role in enabling kernel packet forwarding.