Cisco Certified Network Associate (CCNA) Practice Exam

What is the command to configure an IPv6 address on a router interface using the EUI-64 method?

1. (config-if)#ipv6 address EUI-64

2. (config-if)#ipv6 address FIRST HALF OF IPV ADDRESS/64 eui-64

3. (config-if)#ipv6 address AUTO

4. (config-if)#ipv6 address GENERATE

The correct answer is: (config-if)#ipv6 address FIRST HALF OF IPV ADDRESS/64 eui-64

The command to configure an IPv6 address on a router interface using the EUI-64 method is indeed centered around the proper structure that allows the router to automatically generate the second half of the IPv6 address based on the MAC address of the interface. The command format explicitly includes the first half of the IPv6 address followed by the subnet mask among which the address falls, and then the designation "eui-64" which directs the device to utilize the EUI-64 method to create the remaining portion of the IP address. The reason this command is structured this way is that EUI-64 allows devices to automatically configure their own link-local addresses and globally unique IPv6 addresses without requiring manual configuration. This is particularly useful in scenarios where devices join networks as it enables seamless operation, reducing the administrative burden of managing IP address assignments. Understanding this command and its structure is crucial for network configuration as it emphasizes the automatic generation of addresses, which is a significant feature of IPv6, enhancing both administration and connectivity processes in modern networks.