Question 10 of 239 from exam 200-301: Implementing and Administering Cisco Solutions

Question 10 of 239 from exam 200-301: Implementing and Administering Cisco Solutions


Which command automatically generates an IPv6 address from a specified IPv6 prefix and MAC address of an interface?



A. B. C. D.


The ipv6 address autoconfig command causes the device to perform IPv6 stateless address auto-configuration to discover prefixes on the link and then to add the EUI-64 based addresses to the interface. Addresses are configured depending on the prefixes received in Router Advertisement (RA) messages. The device will listen for RA messages which are transmitted periodically from the router (DHCP Server). This RA message allows a host to create a global IPv6 address from:

Its interface identifier (EUI-64 address)

Link Prefix (obtained via RA)

Note: Global address is the combination of Link Prefix and EUI-64 address

The correct answer is B. ipv6 address 2001:DB8:5:112::/64 eui-64.


IPv6 uses a different mechanism for generating interface identifiers compared to IPv4. One method of generating an IPv6 address is to use EUI-64 (Extended Unique Identifier-64), which is based on the MAC address of the interface.

To use EUI-64 to generate an IPv6 address, the "ipv6 address" command is used with the subnet prefix followed by the "eui-64" keyword. For example, the command "ipv6 address 2001:DB8:5:112::/64 eui-64" will generate an IPv6 address for the interface with a subnet prefix of 2001:DB8:5:112::/64 using EUI-64.

Option A, "ipv6 address dhcp", is used to obtain an IPv6 address from a DHCPv6 server.

Option C, "ipv6 address autoconfig", is used to enable stateless address autoconfiguration, which allows the interface to automatically generate an IPv6 address based on the subnet prefix advertised by a router on the network.

Option D, "ipv6 address 2001:DB8:5:112::2/64 link-local", is used to assign a link-local IPv6 address to the interface with the specified address. This address is used for communication within the local network segment and does not require a router.