I'm new in the IPv6 Topic and Yesterday I was performing some testing on Cisco IOS and Cisco Routers of the addressing type in IPv6 with RIPng, i was testing the following:
- Global Unicast Address
- Link-Local Address
- Anycast Address
- Unique Local Address (which I have a confusion also, but I will post it in other time occasion and question)
Here is a picture of my network topology
The testing occurs in Cisco Packet Tracer 6.2 version.
Objective: What I want to achieve is to use the Anycast Address to 2 DNS server on the Network, 1 on under R1 LAN and 2 under R2 LAN and the rest of the LAN use the Global Unicast for their respective networks and allow end devices to keep sending request to the DNS's if any of them fails.
For some reason that I still don't understand is that the Router pick up the Anycast address for the Internal LAN, instead of the Global Unicast Address when I do Stateless Auto configuration on the host or end devices.
During my research I watch the following YouTube video IPv6-07 Cisco IPv6 Anycast which is why it inspired me to do my testing on my own.
I know that by doing VLAN’s in a L3 Switch it does what I want, but let’s skip that and pretend that I have a plain LAN.
When I do Show IPv6 Interface g0/0 on R1
This is the output that I receive
R1#show int g0/0 GigabitEthernet0/0 is up, line protocol is up (connected) Hardware is CN Gigabit Ethernet, address is 00d0.ff96.cd01 (bia 00d0.ff96.cd01) MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec, reliability 255/255, txload 1/255, rxload 1/255 Encapsulation ARPA, loopback not set Keepalive set (10 sec) Full-duplex, 100Mb/s, media type is RJ45 output flow-control is unsupported, input flow-control is unsupported ARP type: ARPA, ARP Timeout 04:00:00, Last input 00:00:08, output 00:00:05, output hang never Last clearing of "show interface" counters never Input queue: 0/75/0 (size/max/drops); Total output drops: 0 Queueing strategy: fifo Output queue :0/40 (size/max) 5 minute input rate 0 bits/sec, 0 packets/sec 5 minute output rate 149 bits/sec, 0 packets/sec 3 packets input, 224 bytes, 0 no buffer Received 0 broadcasts, 0 runts, 0 giants, 0 throttles 0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort 0 watchdog, 1017 multicast, 0 pause input 0 input packets with dribble condition detected 73 packets output, 39144 bytes, 0 underruns 0 output errors, 0 collisions, 1 interface resets 0 unknown protocol drops 0 babbles, 0 late collision, 0 deferred 0 lost carrier, 0 no carrier 0 output buffer failures, 0 output buffers swapped out
This is the show ipv6 interface brief and show running-config
GigabitEthernet0/0 [up/up] FE80::1 2001:DB8:22::1 2345:: GigabitEthernet0/1 [administratively down/down] GigabitEthernet0/2 [administratively down/down] Serial0/0/0 [up/up] FE80::1 2001:DB8:1::1 Serial0/0/1 [administratively down/down] Serial0/1/0 [administratively down/down] Serial0/1/1 [administratively down/down] Vlan1 [administratively down/down]
R1#show run Building configuration... Current configuration : 1287 bytes ! version 15.1 no service timestamps log datetime msec no service timestamps debug datetime msec no service password-encryption ! hostname R1 ! ! ! ! ! ! ! ! no ip cef ipv6 unicast-routing ! no ipv6 cef ! ipv6 dhcp pool R1 dns-server 2345::9 ! ! ! license udi pid CISCO2911/K9 sn FTX1524RD6F ! ! ! ! ! ! ! ! ! ! ! spanning-tree mode pvst ! ! ! ! ! ! interface GigabitEthernet0/0 no ip address duplex auto speed auto ipv6 address FE80::1 link-local ipv6 address 2001:DB8:22::/64 eui-64 ipv6 address 2345::/64 anycast ipv6 nd other-config-flag ipv6 rip RIP1 enable ipv6 dhcp server R1 ! interface GigabitEthernet0/1 no ip address duplex auto speed auto shutdown ! interface GigabitEthernet0/2 no ip address duplex auto speed auto shutdown ! interface Serial0/0/0 no ip address ipv6 address FE80::1 link-local ipv6 address 2001:DB8:1::1/64 ipv6 rip RIP1 enable clock rate 128000 ! interface Serial0/0/1 no ip address clock rate 2000000 shutdown ! interface Serial0/1/0 no ip address clock rate 2000000 shutdown ! interface Serial0/1/1 no ip address clock rate 2000000 shutdown ! interface Vlan1 no ip address shutdown ! ipv6 router rip RIP1 ! ip classless ! ip flow-export version 9 ! ! ! ! ! ! ! line con 0 ! line aux 0 ! line vty 0 4 login ! ! ! end
P.S:I need Clarification with Link-Local Address, Why i can put the link local on the same device in all it interface many times? It confuse me since R2 have and other link-local address that i can also put on all it interfaces