A network technician has just installed a TFTP server on the administrative segment of the network to store
router and switch configurations. After a transfer attempt to the server is made, the process errors out. Which
of the following is a cause of the error?

A.
Only FTP can be used to copy configurations from switches

B.
Anonymous users were not used to log into the TFTP server

C.
An incorrect password was used and the account is now locked

D.
Port 69 is blocked on a router between the network segments

Explanation:
The question states that the TFTP server is installed on the “administrative segment of the network”. This
implies that the network has multiple segments (subnets) and TFTP server is on a different network segment to
other computers.
For a computer on one subnet to connect to a computer on a different subnet, a router is required to route
traffic between the two subnets. Routers often include firewalls so they can be configured to allow specific
traffic to be routed between the subnets and block unwanted traffic.
TFTP uses UDP port 69. The most likely cause of the connection timeout error in the question is that the
firewall has not been configured to allow traffic using UDP port 69.