Troubleshooting IP Address Issues

A network technician receives reports indicating some users are unable to gain access to any network resources.

During troubleshooting, the technician discovers the workstations have an IP address of 169.254.x.x.

Which of the following is the MOST likely cause?

A.

Expired IP address

B.

Exhausted dynamic scope

C.

Misconfigured VLSM

D.

Rogue DHCP server.

B.

The most likely cause of the issue where some users are unable to gain access to any network resources and their workstations have an IP address of 169.254.x.x is an exhausted dynamic scope.

When a device connects to a network, it typically requests an IP address from a DHCP server. If the DHCP server is not available or does not respond, the device will assign itself an Automatic Private IP Address (APIPA) in the range of 169.254.0.1 to 169.254.255.254. APIPA is a feature that allows a device to automatically assign itself an IP address when it cannot obtain an IP address from a DHCP server.

An exhausted dynamic scope occurs when all available IP addresses in the DHCP scope have been assigned to devices, and there are no more available IP addresses to assign to new devices. When this happens, devices that request an IP address from the DHCP server will not receive a response and will assign themselves an APIPA address in the 169.254.x.x range.

In this scenario, the workstations have assigned themselves an IP address in the 169.254.x.x range because they were unable to obtain an IP address from the DHCP server. This indicates that the DHCP server has likely run out of available IP addresses to assign to new devices.

To resolve this issue, the network technician can increase the size of the DHCP scope or add a new DHCP server to the network to provide additional IP addresses for devices to use.