Volume 1 - Chapter 27: Implementing IPv6 Addressing on Routers

Question 1

What is the correct command to statically configure an IPv6 address of FD90:0100:1234::5 /64 on a router interface?

Answer 1

ipv6 address FC90:0100:1234::0005/64

Note that there is no space between the interface ID and the prefix at the end, routers will not allow you to add a space.

Question 2

What is the command to enable the use of IPv6 routing?

Answer 2

ipv6 unicast-routing

Question 3

True or false, a router will accept IPv6 commands, but not process them if IPv6 routing is not enabled?

Answer 3

True. You can still configure IPv6 without it enabled, but the router will not route any IPv6 packets

Question 4

What are the commands to show information about IPv6 enabled interfaces?

Answer 4

show ipv6 interface brief
show ipv6 interface

Question 5

What is the command to print the IPv6 routing table?

Answer 5

show ipv6 route

Question 6

What method of addressing is used to automatically calculate an IPv6 for an interface based on the MAC address?

Answer 6

Modified EUI-64 (Extended Unique Identifier)

Question 7

Describe the process of EUI-64 calculating an address.

Answer 7

Step 1: The MAC is split into 2 halves of 6 bytes each
Step 2: The hex FFFE is put into the middle
Step 3: The 7th bit of the address is inverted

Question 8

What is the command to set an IPv6 address using EUI-64?

Answer 8

ipv6 address prefix/prefixlength eui-64

Question 9

A technician runs the command show ip interface brief and gets the address attribute of EUI.

What is indicated by this?

Answer 9

That the interface is using an IP address generated by EUI-64.

Question 10

A technician runs the command show ip interface brief and gets the address attribute of TEN.

What is indicated by this?

Answer 10

The IP address is Tentative; currently performing Duplicate Address Detection (DAD).

Question 11

A technician runs the command show ip interface brief and gets the address attribute of CAL.

What is indicated by this?

Answer 11

The IP address is Calendared; the address has a fixed lifetime.

Question 12

A technician runs the command show ip interface brief and gets the address attribute of PRE.

What is indicated by this?

Answer 12

The IP address is Preferred; the address is preferred during its calendar (CAL) lifetime.

Question 13

When is it likely to see IPv6 attributes of CAL or PRE on an interface?

Answer 13

When the address associated with the interface is using SLAAC or DHCP

Question 14

What is the command to assign an IPv6 address on an interface using DHCP?

Answer 14

ipv6 address dhcp

Question 15

What is the command to assign an IPv6 address on an interface using SLAAC?

Answer 15

ipv6 address autoconfig

Question 16

What is the purpose of IPv6 Link-Local Addresses?

Answer 16

To send and receive data on a point-to-point link before a GUA or ULA has been assigned

Question 17

All interfaces that support IPv6 must have a ___ configured.

Answer 17

A Link-Local Address

Question 18

How do routers generate IPv6 link-local addresses?

Answer 18

Using EUI-64

Question 19

What is the prefix associated with an IPv6 link-local address?

Answer 19

FE80::/10

Question 20

What is the command to statically assign a link-local address to an interface?

Answer 20

ipv6 address address link-local

Question 21

Describe the difference between a router using SLAAC to generate an IPv6 address, versus an address being statically configured as EUI-64

Answer 21

In both scenarios, EUI is used. However, with SLAAC the interface dynamically learns the prefix and prefix length.

Whereas you are statically configuring the prefix and dynamically generating only the IID otherwise.

Question 22

What is the command used to generate an IPv6 link-local address on an interface, but to purposefully leave it without a GUA or ULA address?

Answer 22

ipv6 enable

Question 23

What type of IPv6 multicast scope describes a packet that stays within the same host?

Answer 23

Interface-Local

Question 24

What type of IPv6 multicast scope describes a packet that stays within the same physical link and cannot be routed?

Answer 24

Link-Local

Question 25

What type of IPv6 multicast scope describes a packet that cannot be forwarded to the WAN?

Answer 25

Site-Local

Question 26

What type of IPv6 multicast scope describes a packet that stays within the organization?

Answer 26

Organization-Local

Question 27

What type of IPv6 multicast scope describes a packet that has no boundries/restrictions?

Answer 27

Global

Question 28

What is the prefix and prefix length for a Solicited-Node Multicast Address?

Answer 28

FF02::1:FF/104

Question 29

How does a router dynamically generate a Solicited-Node Multicast Address?

Answer 29

By appending the last 6 hex-digits of the currently configured ULA or GUA IP to the address FF02::1:FF/104

Question 30

A router generates a solicited-node multicast address for ___ address on an interface.

Answer 30

ULA, GUA, and Link-Local

Question 31

What IPv6 address is designated as “unspecified”?

Answer 31

::

Question 32

What is a restriction of the unspecified IPv6 address?

Answer 32

It can only be used as a source address

Question 33

What IPv6 address is designated as the loopback address?

Answer 33

::1

Question 34

What type of IPv6 address is identically configured across multiple routers and used when devices want to send data to a group of routers that all share a service?

Answer 34

Anycast

Question 35

What is the command to configure an IPv6 anycast address on an interface?

Answer 35

ipv6 address address/prefix anycast