12.9.2 Lab – Configure IPv6 Addresses on Network Devices (Answers)

 Objectives

Part 1: Establish Topology and Configure Basic Router and Switch Settings 

Part 2: Manually Configure IPv6 Addresses

Part 3: Verify End-to-End Connectivity 

Context / Scenario

In this lab, you will setup IPv6 addresses on host and device interfaces. The show command will display IPv6 unicast addresses. Using ping and traceroute commands, you will also test end-to-end connection.Note: Cisco 4221 routers running Cisco IOS XE Release 16.9.4 are used in CCNA hands-on labs (universalk9 image). The lab switches are Cisco Catalyst 2960s running Cisco IOS Release 15.2(2). (lanbasek9 image). Other routers, switches, and versions of Cisco IOS may be used. Depending on the model and Cisco IOS version, the available commands and output may differ from what is demonstrated in the labs. For the correct interface identifiers, consult the Router Interface Summary Table at the end of the lab. Note: Ensure that all startup configurations have been removed from the routers and switches. If you are unsure, contact your instructor.

Instructor Note: Refer to the Instructor Lab Manual for device initialization and reloading procedures.

Note: IPv6 is not supported by the default 2960 Switch Database Manager (SDM) template. Before assigning an IPv6 address to the VLAN 1 SVI, it may be essential to execute the sdm prefer dual-ipv4-and-ipv6 default command to allow IPv6 addressing.

Note: The default bias template used by the Switch Database Manager (SDM) lacks IPv6 address support. Verify that SDM is using either the dual-ipv4-and-ipv6 or lanbase-routing template. After rebooting, the updated template will be used.

S1# show sdm prefer

Follow these steps to assign the dual-ipv4-and-ipv6 template as the default SDM template:

S1# configure terminal

S1(config)# sdm prefer dual-ipv4-and-ipv6 default

S1(config)# end

S1# reload

Essential Resources

1 Routing (Cisco 4221 with Cisco IOS XE Release 16.9.4 universal image or comparable)

1 Switch (Cisco 2960 with Cisco IOS Release 15.2(2) lanbasek9 or equivalent)

◾2 PCs (Windows with terminal emulation program, such as Tera Term)

Console cables used to configure Cisco IOS devices using their console ports

Ethernet wires as seen in the network topology

Note: The Gigabit Ethernet interfaces on Cisco 4221 routers are auto-detecting, therefore an Ethernet straight-through connection may be utilised between the router and PC-B. If utilising a different Cisco router model, an Ethernet crossover connection may be required.

Instructions

Part 1: Wiring the Network and Configuring the Router and Switch

After wiring the network and initialising and reloading the router and switch, do the following steps:

Configure the router in Step 1.

Assign a hostname and configure the device's fundamental settings.

Configure the switch in Step 2.

Assign a hostname and configure the device's fundamental settings.

Part 2: Manually Configure IPv6 Addresses

Assign IPv6 addresses to Ethernet connections on R1.

Launch configuration display

R1(config)

# interface g0/0/0

R1(config-if)# ipv6 address 2001:db8:acad:a::1/64

R1(config-if)# no shutdown

R1(config-if)

# interface g0/0/1

R1(config-if)

# ipv6 address 2001:db8:acad:1::1/64

R1(config-if)

# no shutdown

R1(config-if)

# end

As defined in RFC 3849, the IPv6 global prefix 2001:db8::/32 is reserved for use in documentation. Verify that each interface has the right IPv6 unicast address allocated.

R1# show ipv6 interface brief

Em0/0                  [administratively down/down]

    unassigned

GigabitEthernet0/0/0     [up/up]

    FE80::D68C:B5FF:FECE:A0C0

    2001:DB8:ACAD:A::1

GigabitEthernet0/0/1     [up/up]

    FE80::D68C:B5FF:FECE:A0C1

    2001:DB8:ACAD:1::1

<output omitted>

Note: The link-local address (fe80::) presented is based on EUI-64 addressing, which utilises the interface's Media Access Control (MAC) address to automatically generate a 128-bit IPv6 link-local address. To obtain the link-local address on the interface to match the global unicast address, manually input the link-local addresses on each Ethernet interface on R1.

R1# config t

Enter configuration commands, one per line. End with CNTL/Z.

R1(config)# interface g0/0/0

R1(config-if)# ipv6 address fe80::1 link-local

R1(config-if)# interface g0/0/1

R1(config-if)# ipv6 address fe80::1 link-local

R1(config-if)# end

Note: Each router interface belongs to a separate network. Packets with a link-local address never leave the local network; therefore, you can use the same link-local address on both interfaces.

d. Use a command of your choice to verify that the link-local address has been changed to fe80::1.

R1# show ipv6 interface g0/0/0

GigabitEthernet0/0/0 is up, line protocol is up

  IPv6 is enabled, link-local address is FE80::1

  No Virtual link-local address(es):

  Global unicast address(es):

    2001:DB8:ACAD:A::1, subnet is 2001:DB8:ACAD:A::/64 

  Joined group address(es):

    FF02::1

    FF02::1:FF00:1

  MTU is 1500 bytes

<output omitted>

Which two multicast groups have been assigned to interface G0/0/0?

The all-nodes multicast group (FF02::1) and the Solicited Nodes multicast group (ff02::1:ff00:1).

Step 2: Enable IPv6 routing on R1.

a. On a PC-B command prompt, enter the ipconfig command to examine IPv6 address information assigned to the PC interface.

Has an IPv6 unicast address been assigned to the network interface card (NIC) on PC-B?

No

b. Enable IPv6 routing on R1 using the IPv6 unicast-routing command.

R1 # configure terminal

R1(config)# ipv6 unicast-routing

R1(config)# exit

c. Use a command to verify the new multicast group are assigned to interface G0/0/0. Notice that the all-router multicast group (ff02::2) now appears for interface G0/0/0.

Note: This will allow the PCs to obtain their IP address and default gateway information automatically using Stateless Address Autoconfiguration (SLAAC).

R1# show ipv6 interface g0/0/0

GigabitEthernet0/0/0 is up, line protocol is up

  IPv6 is enabled, link-local address is FE80::1

  No Virtual link-local address(es):

  Global unicast address(es):

    2001:DB8:ACAD:A::1, subnet is 2001:DB8:ACAD:A::/64 [EUI]

  Joined group address(es):

    FF02::1

    FF02::2

    FF02::1:FF00:1

  MTU is 1500 bytes

<partial output omitted>

Hosts use stateless autoconfig for addresses.

d. Now that R1 is part of the all-router multicast group FF02::2, re-issue the ipconfig command on PC-B and examine the IPv6 address information.

Why did PC-B receive the Global Routing Prefix and Subnet ID that you configured on R1?

On R1 all IPv6 interfaces are now part of the All-router multicast group, FF02::2. This allows it to send Router Advertisement (RA) messages with the Global Network Address and Subnet ID information to all nodes on the LAN. Notice that R1 also sent the link-local address, fe80::1, as the Default Gateway. The PCs will receive their IPv6 addresses and default gateway via SLAAC as long as the advertised prefix length is 64 bits .

Step 3: Assign IPv6 addresses to the management interface (SVI) on S1.

a. Assign the IPv6 address for S1. Also assign a link-local address for this interface.

S1(config)# interface vlan 1

S1(config-if)# ipv6 address 2001:db8:acad:1::b/64

S1(config-if)# ipv6 address fe80::b link-local

S1(config-if)# end

b. Use a command of your choice to verify that the IPv6 addresses are properly assigned to the management interface.

S1# show ipv6 interface vlan1

Vlan1 is up, line protocol is up

  IPv6 is enabled, link-local address is FE80::B

  No Virtual link-local address(es):

  Global unicast address(es):

    2001:DB8:ACAD:1::B, subnet is 2001:DB8:ACAD:1::/64

  Joined group address(es):

    FF02::1

    FF02::1:FF00:B

  MTU is 1500 bytes

  ICMP error messages limited to one every 100 milliseconds

  ICMP redirects are enabled

  ICMP unreachables are sent

  Output features: Check hwidb

  ND DAD is enabled, number of DAD attempts: 1

  ND reachable time is 30000 milliseconds (using 30000)

  ND NS retransmit interval is 1000 milliseconds

Step 4: Assign static IPv6 addresses to the PCs.

a. Open the Ethernet Properties window on for each PC and assign IPv6 addressing.

b. Verify both PCs have the correct IPv6 address information. Each PC should have two Global IPv6 addresses: one static and one SLACC

Part 3: Verify End-to-End Connectivity

From PC-A, ping fe80::1. This is the link-local address assigned to G0/0/1 on R1.

Ping the S1 management interface from PC-A.

Use the tracert command on PC-A to verify that you have end-to-end connectivity to PC-B.

From PC-B, ping PC-A.

From PC-B, ping the link-local address for G0/0/0 on R1.

Note: If end-to-end connectivity is not established, troubleshoot your IPv6 address assignments to verify that you entered the addresses correctly on all devices.

Reflection Questions

1.Why is it possible to give the same link-local address to both Ethernet interfaces on R1?

Since link-local packets never leave the local network, the same link-local address may be used on an interface linked with a different local network.

2.What is the Subnet ID associated with the IPv6 unicast address 2001:db8:acaa:aaa:1234/64?

0 (zero) or 0000 (zeros). The fourth octet of an IPv6 address with a prefix of /64 is the Subnet ID. In the example, the fourth octet is composed entirely of zeros, and the IPv6 Omitting All 0 Segment rule uses a double colon to represent the Subnet ID and the first two octets of the Interface ID. Therefore, the subnet associated with the Global unicast address 2001:acad::aaaa:1234/64 is 2001:db8:::/64.

Note: To determine how the router is setup, examine the interfaces to determine the kind of router and the number of interfaces. There is no practical method to list all configuration choices for each router type. This table contains IDs for the device's various Ethernet and Serial interface combinations. The table does not list any more interface types, despite the fact that certain routers may include them. Such an example may be an ISDN BRI interface. The text included in parentheses is the legal shorthand that may be used to represent the interface in Cisco IOS instructions.

Device Configs

Router R1 (After part 1 of this lab)

R1# show run

Building configuration...

Current configuration : 1443 bytes

!

version 15.2

service timestamps debug datetime msec

service timestamps log datetime msec

service password-encryption

!

hostname R1

!

boot-start-marker

boot-end-marker

!

!

enable secret 4 06YFDUHH61wAE/kLkDq9BGho1QM5EnRtoyr8cHAUg.2

!

no aaa new-model

memory-size iomem 15

!

no ip domain lookup

ip cef

no ipv6 cef

multilink bundle-name authenticated

!

!

interface Embedded-Service-Engine0/0

no ip address

shutdown

!

interface GigabitEthernet0/0/0

no ip address

shutdown

duplex auto

speed auto

!

interface GigabitEthernet0/0/1

no ip address

shutdown

duplex auto

speed auto

!

interface Serial0/0/0

no ip address

shutdown

clock rate 2000000

!

interface Serial0/0/1

no ip address

shutdown

!

ip forward-protocol nd

!

no ip http server

no ip http secure-server

!

control-plane

!

banner motd ^C

**********************************************

* Warning: Unauthorized access is prohibited! *

**********************************************

^C

!

line con 0

password 7 01100F175804

login

line aux 0

line 2

no activation-character

no exec

transport preferred none

transport input all

transport output pad telnet rlogin lapb-ta mop udptn v120 ssh

stopbits 1

line vty 0 4

password 7 104D000A0618

login

transport input all

!

scheduler allocate 20000 1000

!

end

Switch S1 (After part 1 of this lab)

S1# show run

Building configuration...

Current configuration : 1624 bytes

!

version 15.0

no service pad

service timestamps debug datetime msec

service timestamps log datetime msec

service password-encryption

!

hostname S1

!

boot-start-marker

boot-end-marker

!

enable secret 4 06YFDUHH61wAE/kLkDq9BGho1QM5EnRtoyr8cHAUg.2

!

no aaa new-model

system mtu routing 1500

!

!

no ip domain-lookup

!

spanning-tree mode pvst

spanning-tree extend system-id

!

vlan internal allocation policy ascending

!

interface FastEthernet0/1

!

interface FastEthernet0/2

!

interface FastEthernet0/3

!

interface FastEthernet0/4

!

interface FastEthernet0/5

!

interface FastEthernet0/6

!

interface FastEthernet0/7

!

interface FastEthernet0/8

!

interface FastEthernet0/9

!

interface FastEthernet0/10

!

interface FastEthernet0/11

!

interface FastEthernet0/12

!

interface FastEthernet0/13

!

interface FastEthernet0/14

!

interface FastEthernet0/15

!

interface FastEthernet0/16

!

interface FastEthernet0/17

!

interface FastEthernet0/18

!

interface FastEthernet0/19

!

interface FastEthernet0/20

!

interface FastEthernet0/21

!

interface FastEthernet0/22

!

interface FastEthernet0/23

!

interface FastEthernet0/24

!

interface GigabitEthernet0/1

!

interface GigabitEthernet0/2

!

interface Vlan1

no ip address

!

ip http server

ip http secure-server

!

banner motd ^C

**********************************************

* Warning: Unauthorzed access is prohibited! *

**********************************************

^C

!

line con 0

password 7 121A0C041104

login

line vty 0 4

password 7 121A0C041104

login

line vty 5 15

password 7 121A0C041104

login

!

end

Router R1 (Final)

R1# show run

Building configuration...

Current configuration : 1577 bytes

!

version 15.2

service timestamps debug datetime msec

service timestamps log datetime msec

service password-encryption

!

hostname R1

!

boot-start-marker

boot-end-marker

!

enable secret 4 06YFDUHH61wAE/kLkDq9BGho1QM5EnRtoyr8cHAUg.2

!

no aaa new-model

memory-size iomem 15

!

no ip domain lookup

ip cef

ipv6 unicast-routing

ipv6 cef

multilink bundle-name authenticated

!

!

interface Embedded-Service-Engine0/0

no ip address

shutdown 

!

interface GigabitEthernet0/0/0

no ip address

duplex auto

speed auto

ipv6 address fe80::1 link-local

ipv6 address 2001:db8:acad:a::1/64

!

interface GigabitEthernet0/0/1

no ip address

duplex auto

speed auto

ipv6 address fe80::1 link-local

ipv6 address 2001:db8:acad:1::1/64

!

interface Serial0/0/0

no ip address

shutdown

clock rate 2000000

!

interface Serial0/0/1

no ip address

shutdown 

!

ip forward-protocol nd

!

no ip http server

no ip http secure-server

!

control-plane

!

banner motd ^C

**********************************************

* Warning: Unauthorzed access is prohibited! *

**********************************************

^C

!

line con 0

password 7 01100F175804

login

line aux 0

line 2

no activation-character

no exec

transport preferred none

transport input all

transport output pad telnet rlogin lapb-ta mop udptn v120 ssh

stopbits 1

line vty 0 4

password 7 104D000A0618

login

transport input all

!

scheduler allocate 20000 1000

!

end

Switch S1 (Final)

* Warning: Unauthorzed access is prohibited! *

**********************************************

^C

!

line con 0

password 7 121A0C041104

login

line vty 0 4

password 7 121A0C041104

login

line vty 5 15

password 7 121A0C041104

login

!

end