Step 2. Manual configuration of global unicast and link-local addresses

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1 Lab: DHCPv6 CIS 116 IPv6 Fundamentals Enter your answers to the questions in this lab using Canvas Quiz DHCPv6 Lab. Step 1. Setup a. Log into NetLab: ccnp.bayict.cabrillo.edu b. Schedule IPv6 Pod 1: no configs loaded (clean) c. Configure each router with the following commands: Router> enable Router# conf t Router(config)# hostname <R1, R2 or R2> R1(config)# no ip domain-lookup R1(config)# line con 0 R1(config-line)# logging synchronous R1(config-line)# exec-timeout 0 0 Note: If using the interface configurations from a previous lab, make sure the router has not been configured as an IPv6 router: Router(config)# no ipv6 unicast-routing Step 2. Manual configuration of global unicast and link-local addresses Note: R2 and R3 are not used in this lab, but the configurations are provided for your enjoyment. J R1 conf t R1(config-if)# ipv6 address 2001:db8:cab:828::1/64 R1(config-if)# ipv6 address fe80::828:1 link-local R1(config-if)# no shutdown R1(config-if)# exit R1(config)# interface g 0/1 R1(config-if)# ipv6 address 2001:db8:cab:1000::1/64 R1(config-if)# ipv6 address fe80::1 link-local

2 R1(config-if)# no shutdown R1(config-if)# end Verify show ipv6 interface brief GigabitEthernet0/0 [up/up] FE80::828:1 2001:DB8:CAB:828::1 GigabitEthernet0/1 [up/up] FE80::1 2001:DB8:CAB:1000::1 Step 3. Enabling the router as an IPv6 router and Configuring EIGRP for IPv6 Using the show ipv6 interface g0/0 command, examine the multicast addresses on R1 prior to it being configured as an IPv6 router. show ipv6 interface g0/0 GigabitEthernet0/0 is up, line protocol is up IPv6 is enabled, link-local address is FE80::828:1 No Virtual link-local address(es): Global unicast address(es): 2001:DB8:CAB:828::1, subnet is 2001:DB8:CAB:828::/64 Joined group address(es): FF02::1 FF02::FB FF02::1:FF00:1 FF02::1:FF28:1 MTU is 1500 bytes ICMP error messages limited to one every 100 milliseconds ICMP redirects are enabled ICMP unreachables are sent ND DAD is enabled, number of DAD attempts: 1 ND reachable time is milliseconds (using 30000) ND NS retransmit interval is 1000 milliseconds Configure all R1 as an IPv6 router: R1(config)# ipv6 unicast-routing Verify R1 has joined the all IPv6 routers multicast group using the show ipv6 interface g 0/0 command. Notice the additional Router Advertisement information. show ipv6 interface g 0/0 GigabitEthernet0/0 is up, line protocol is up IPv6 is enabled, link-local address is FE80::828:1 No Virtual link-local address(es):

3 Global unicast address(es): 2001:DB8:CAB:828::1, subnet is 2001:DB8:CAB:828::/64 Joined group address(es): FF02::1 FF02::2 FF02::FB FF02::1:FF00:1 FF02::1:FF28:1 MTU is 1500 bytes ICMP error messages limited to one every 100 milliseconds ICMP redirects are enabled ICMP unreachables are sent ND DAD is enabled, number of DAD attempts: 1 ND reachable time is milliseconds (using 30000) ND advertised reachable time is 0 (unspecified) ND advertised retransmit interval is 0 (unspecified) ND router advertisements are sent every 200 seconds ND router advertisements live for 1800 seconds ND advertised default router preference is Medium Hosts use stateless autoconfig for addresses. Step 4. Examining the RA message using debug ipv6 nd Use the debug ipv6 nd command to view the RA message sent on G 0/0. debug ipv6 nd ICMP Neighbor Discovery events debugging is on ICMPv6-ND: (GigabitEthernet0/0,FE80::828:1) send RA to FF02::1 ICMPv6-ND: (GigabitEthernet0/0,FE80::828:1) Sending RA (1800) to FF02::1 ICMPv6-ND: MTU = 1500 ICMPv6-ND: prefix 2001:DB8:CAB:828::/64 [LA] / undebug all Question 1: Using the output above, which of the following flags are set to 1 (on)? Question 2: Using the output above, how will hosts dynamically obtain their IPv6 addressing information? Question 3: Using the output above, which of the following information is contained in this RA message? Stateless DHCPv6 Step 5. Configure R1 s RA message to advertise stateless DHCPv6 Configure R1 s G0/0 interface to suggest to hosts that other configuration information is available from a stateless DHCPv6 server. R1(config-if)# ipv6 nd other-config-flag Question 4: The command above sets which flag to 1 (on)?

4 Use the debug ipv6 nd command to verify that the O flag has been set. debug ipv6 nd ICMP Neighbor Discovery events debugging is on *Nov 5 21:24:45.175: ICMPv6-ND: (GigabitEthernet0/0,FE80::828:1) send RA to FF02::1 *Nov 5 21:24:45.175: ICMPv6-ND: Other stateful *Nov 5 21:24:45.175: ICMPv6-ND: (GigabitEthernet0/0,FE80::828:1) Sending RA (1800/O) to FF02::1 *Nov 5 21:24:45.175: ICMPv6-ND: MTU = 1500 *Nov 5 21:24:45.175: ICMPv6-ND: prefix 2001:DB8:CAB:828::/64 [LA] / undebug all Use show ipv6 interface g 0/0 to verify the RA is suggesting SLAAC and stateless DHCPv6. show ipv6 interface g 0/0 GigabitEthernet0/0 is up, line protocol is up IPv6 is enabled, link-local address is FE80::828:1 No Virtual link-local address(es): Global unicast address(es): 2001:DB8:CAB:828::1, subnet is 2001:DB8:CAB:828::/64 Joined group address(es): FF02::1 FF02::2 FF02::A FF02::FB FF02::1:2 FF02::1:FF00:1 FF02::1:FF28:1 FF05::1:3 MTU is 1500 bytes ICMP error messages limited to one every 100 milliseconds ICMP redirects are enabled ICMP unreachables are sent ND DAD is enabled, number of DAD attempts: 1 ND reachable time is milliseconds (using 30000) ND advertised reachable time is 0 (unspecified) ND advertised retransmit interval is 0 (unspecified) ND router advertisements are sent every 200 seconds ND router advertisements live for 1800 seconds ND advertised default router preference is Medium Hosts use stateless autoconfig for addresses. Hosts use DHCP to obtain other configuration. Step 6. Configure R1 as a stateless DHCPv6 server Configure R1 s as a stateless DHCPv6 server on its G0/0 interface. R1(config)# ipv6 dhcp pool IPV6-STATELESS-SERVER R1(config-dhcpv6)# dns-server 2001:db8:cab:3::9999 R1(config-dhcpv6)# domain-name

5 R1(config-dhcpv6)# exit R1(config-if)# ipv6 dhcp server IPV6-STATELESS-SERVER R1(config-if)# end Step 7. Examine the configuration of WinPC 1 Use the ipconfig /all command on WinPC 1 and examine the addressing information. Question 5: How did WinPC 1 create its GUA address? Question 6: How did WinPC 1 obtain its default gateway? Question 7: How did WinPC 1 obtain its DNS server address? Question 8: How did WinPC 1 obtain its DNS Suffix? Question 9: What is used to uniquely identify WinPC 1 as a DHCPv6 client?

6 Question 10: What is used to uniquely identify the interface on WinPC 1 as a DHCPv6 client? Step 8. Verify the configuration of R1 as stateless DHCPv6 server Verify stateless DHCPv6 operations on R1. show ipv6 dhcp This device's DHCPv6 unique identifier(duid): EF900 show ipv6 dhcp interface g 0/0 GigabitEthernet0/0 is in server mode Using pool: IPV6-STATELESS-SERVER Preference value: 0 Hint from client: ignored Rapid-Commit: disabled Question 12: What does the Rapid-Commit: disabled refer to? show ipv6 dhcp pool DHCPv6 pool: IPV6-STATELESS-SERVER DNS server: 2001:DB8:CAB:3::9999 Domain name: Active clients: 0 Notice the IPV6-STATELESS-SERVER pool states R1 has no active clients. This is because this is for a stateless DHCPv6 server and no state is maintained. Step 9. Configure the rapid-commit option on R1 Configure R1 to use the rapid-commit option. R1(config-if)# ipv6 dhcp server IPV6-STATELESS-SERVER rapid-commit R1(config-if)# end Step 10. Testing the rapid-commit option on WinPC 1 Windows 7 does not support Rapid commit. We can verify that the rapid commit option is not used when we see the DHCPv6 messages exchanged using debug ipv6 dhcp. For a listing of client/server DHCPv6 options: debug ipv6 dhcp IPv6 DHCP debugging is on

7 Reset the Ethernet adapter on WinPC 1: 1. Start > Network > Network and Sharing Center > Change adapter settings > right-click on Local Area Connection > Disable 2. right-click on Local Area Connection > Enable IPv6 DHCP: Received INFORMATION-REQUEST from FE80::D0F8:9FF6:4201:7086 on GigabitEthernet0/0 IPv6 DHCP: Option VENDOR-CLASS(16) is not processed IPv6 DHCP: Using interface pool IPV6-STATELESS-SERVER IPv6 DHCP: Source Address from SAS FE80::828:1 IPv6 DHCP: Sending REPLY to FE80::D0F8:9FF6:4201:7086 on GigabitEthernet0/0 undebug all Notice that WinPC 1 is sending an INFORMATION-REQUEST which not otherwise be sent if Windows 7 supported the rapid commit option. Stateful DHCPv6 Step 11. Removing the stateless pool option from R1 s G0/0 interface Let s look at R1 s current configuration: show running-config <partial output> ipv6 unicast-routing ipv6 dhcp pool IPV6-STATELESS-SERVER dns-server 2001:DB8:CAB:3::9999 domain-name interface GigabitEthernet0/0 no ip address duplex auto speed auto ipv6 address FE80::828:1 link-local ipv6 address 2001:DB8:CAB:828::1/64 ipv6 nd other-config-flag ipv6 eigrp 1 ipv6 dhcp server IPV6-STATELESS-SERVER rapid-commit! <end of output> We can leave the IPv6 DHCP pool IPV6-STATELESS-SERVER but we need to remove this function from R1 s G0/0 interface. We will be configuring the Managed Address Configuration (M) flag but so there isn t any ambiguity, we will remove the Other Configuration (O) flag from being set in the RA on the G0/0 interface.

8 R1(config-if)# no ipv6 dhcp server IPV6-STATELESS-SERVER rapid-commit R1(config-if)# no ipv6 nd other-config-flag R1(config-if)# Step 12. Configure R1 s RA message to advertise stateful DHCPv6 Configure R1 s G0/0 interface to suggest to hosts all addressing information (except the default gateway address) is available from a stateful DHCPv6 server. R1(config-if)# ipv6 nd managed-config-flag Question 13: The command above sets which flag to 1 (on)? Use the debug ipv6 nd command to verify that the M flag has been set (on) and sent in the RA. debug ipv6 nd ICMP Neighbor Discovery events debugging is on ICMPv6-ND: (GigabitEthernet0/0,FE80::828:1) send RA to FF02::1 ICMPv6-ND: Managed address ICMPv6-ND: (GigabitEthernet0/0,FE80::828:1) Sending RA (1800/M) to FF02::1 ICMPv6-ND: MTU = 1500 ICMPv6-ND: prefix 2001:DB8:CAB:828::/64 [LA] / undebug all Question 14: What other flag is also to 1 (on) by default? Use show ipv6 interface g 0/0 to verify the RA is suggesting stateful DHCPv6. show ipv6 interface g 0/0 GigabitEthernet0/0 is up, line protocol is up IPv6 is enabled, link-local address is FE80::828:1 No Virtual link-local address(es): Global unicast address(es): 2001:DB8:CAB:828::1, subnet is 2001:DB8:CAB:828::/64 Joined group address(es): FF02::1 FF02::2 FF02::A FF02::FB FF02::1:FF00:1 FF02::1:FF28:1 MTU is 1500 bytes ICMP error messages limited to one every 100 milliseconds ICMP redirects are enabled ICMP unreachables are sent ND DAD is enabled, number of DAD attempts: 1 ND reachable time is milliseconds (using 30000) ND advertised reachable time is 0 (unspecified) ND advertised retransmit interval is 0 (unspecified)

9 ND router advertisements are sent every 200 seconds ND router advertisements live for 1800 seconds ND advertised default router preference is Medium Hosts use DHCP to obtain routable addresses. Step 13. Configure R1 as a stateless DHCPv6 server Configure R1 s as a stateless DHCPv6 server on its G0/0 interface. R1(config)# ipv6 dhcp pool IPV6-STATEFUL-SERVER R1(config-dhcpv6)# address prefix 2001:db8:cab:828:beef::/80 R1(config-dhcpv6)# dns-server 2001:db8:cab:828:3::9999 R1(config-dhcpv6)# domain-name R1(config-dhcpv6)# exit R1(config-if)# ipv6 dhcp server IPV6-STATEFUL-SERVER R1(config-if)# Step 14. Examine the configuration of WinPC 1 Reset the Ethernet adapter on WinPC 1: 1. Start > Network > Network and Sharing Center > Change adapter settings > right-click on Local Area Connection > Disable 2. right-click on Local Area Connection > Enable Use the ipconfig /all command on WinPC 1 and examine the addressing information.

10 Notice the IPv6 GUA address that contains beef at the beginning of the Interface ID. Question 15: How many total Global Unicast Addresses does WinPC 1 have? Question 16: How were the other two GUA addresses created (the two that do not contain beef at the beginning of the Interface ID)? Question 17: Why did WinPC 1 use stateful DHCPv6 to obtain an address and SLAAC to create other addresses (public and temporary)? Step 15. Verify the configuration of R1 as stateful DHCPv6 server Verify stateful DHCPv6 operations on R1. show ipv6 dhcp interface g 0/0 GigabitEthernet0/0 is in server mode Using pool: IPV6-STATEFUL-SERVER Preference value: 0

11 Hint from client: ignored Rapid-Commit: disabled The show ipv6 dhcp binding command shows the link-local address of WinPC 1 and its assigned global unicast address. show ipv6 dhcp binding Client: FE80::D0F8:9FF6:4201:7086 DUID: A5FDAB CC045 Username : unassigned VRF : default IA NA: IA ID 0x0E005056, T , T Address: 2001:DB8:CAB:828:BEEF:44BE:ED9E:FD76 preferred lifetime 86400, valid lifetime expires at Nov :38 AM ( seconds) Step 16. Removing SLAAC from the RA message In most environments that use stateful DHCPv6, we don t want devices to create their own addresses using SLAAC. This can be best accomplished by simply removing the A Flag for the 2001:db8:cab:828::/64 prefix from the RA message on G0/0. R1(config-if)# ipv6 nd prefix 2001:db8:cab:828::/64 no-autoconfig R1(config-if)# end Verify the removal of the A flag using debug ipv6 nd. Notice the absence of the A flag. debug ipv6 nd ICMP Neighbor Discovery events debugging is on ICMPv6-ND: (GigabitEthernet0/0,FE80::828:1) send RA to FF02::1 ICMPv6-ND: Managed address ICMPv6-ND: (GigabitEthernet0/0,FE80::828:1) Sending RA (1800/M) to FF02::1 ICMPv6-ND: MTU = 1500 ICMPv6-ND: prefix 2001:DB8:CAB:828::/64 [L] / undebug all Question 18: Is the prefix still included? Question 19: Is the on-link (L) flag still set to 1 (on)? If the prefix was not included and/or the on-link (L) flag was set to 0 (off), devices wouldn t know what subnet they are on and would send all packets to the default gateway (router). Step 17. Re-examine the configuration of WinPC 1 Reset the Ethernet adapter on WinPC 1: 1. Start > Network > Network and Sharing Center > Change adapter settings > right-click on Local Area Connection > Disable 2. right-click on Local Area Connection > Enable

12 Use the ipconfig /all command on WinPC 1 and examine the addressing information. Question 20: Did WinPC 1 create any SLAAC address(es)?