nerdexam
GIAC

GCFA · Question #28

You work as a Network Administrator for Net Perfect Inc. The company has a Windows Server 2008 network environment. The network is configured as a Windows Active Directory-based single forest single…

Because the server cannot ping its own loopback address, the fault is entirely local to the server itself, eliminating all external network components as the cause - a failed NIC is the most consistent explanation.

Threat Hunting & Timeline Analysis

Question

You work as a Network Administrator for Net Perfect Inc. The company has a Windows Server 2008 network environment. The network is configured as a Windows Active Directory-based single forest single domain network. The network is configured on IP version 6 protocol. All the computers on the network are connected to a switch device. One day, users complain that they are unable to connect to a file server. You try to ping the client computers from the server, but the pinging fails. You try to ping the server's own loopback address, but it fails to ping. You restart the server, but the problem persists. What is the most likely cause?

Options

  • AThe cable that connects the server to the switch is broken.
  • BAutomatic IP addressing is not working.
  • CThe switch device is not working.
  • DThe server is configured with unspecified IP address.
  • EThe server's NIC is not working.

Why each option

Because the server cannot ping its own loopback address, the fault is entirely local to the server itself, eliminating all external network components as the cause - a failed NIC is the most consistent explanation.

AThe cable that connects the server to the switch is broken.

A broken cable would prevent communication with external hosts but would never cause loopback ping failures, since loopback traffic is processed entirely within the server and never reaches a physical cable.

BAutomatic IP addressing is not working.

An automatic IP addressing failure would result in a missing or APIPA address affecting external connectivity, but the loopback address is statically assigned by the OS and would still respond.

CThe switch device is not working.

A non-functioning switch would isolate the server from the rest of the network but would have no effect on the server's internal loopback interface.

DThe server is configured with unspecified IP address.

An unspecified IPv6 address (::/128) would break external connectivity but would not prevent the loopback address (::1) from responding to pings.

EThe server's NIC is not working.

Concept tested: Network loopback failure diagnosis and NIC troubleshooting

Source: https://learn.microsoft.com/en-us/troubleshoot/windows-server/networking/troubleshoot-tcp-ip-connectivity

Topics

#NIC failure#loopback address#network troubleshooting#IPv6 diagnostics

Community Discussion

No community discussion yet for this question.

Full GCFA Practice