ospfv3 w/rip... cont...

there's a lot going on in this seemingly simple topology...

r2#sh run int f0/0
interface FastEthernet0/0
 no ip address
 speed auto
 duplex auto
 ipv6 address 2003::1/124
 ipv6 enable
 ipv6 ospf 1 area 0

it connects to 2003::2/124 on r3

this makes perfect sense to my simple ipv4 mind...

r2#ping ipv6 2003::2   
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 2003::2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 4/8/24 ms

why it makes sense? ::1 connects to ::2...

according to wiki:

A link-local address is an Internet Protocol address that is intended only for communications within the segment of a local network (a link) or a point-to-point connection that a host is connected to. Routers do not forward packets with link-local addresses.

and:

fe80::/10 has been reserved for link-local addressing

knowing this we can step out of the ipv4 mindset...

first if we simply enable ipv6 on the two interfaces, along with ipv6 ospf the ospf link will come up...

r3#sh run int f0/0
Building configuration...

Current configuration : 106 bytes
!
interface FastEthernet0/0
 no ip address
 speed auto
 duplex auto
 ipv6 enable
 ipv6 ospf 1 area 0
end

r2(config-if)#do sh run int f0/0
Building configuration...

Current configuration : 73 bytes
!
interface FastEthernet0/0
 no ip address
 speed auto
 duplex auto
end

r2(config-if)#ipv6 enable
r2(config-if)#ipv6 ospf 1 area 0
r2(config-if)#
*Sep 23 10:15:49: %OSPFv3-5-ADJCHG: Process 1, Nbr 2.2.2.2 on FastEthernet0/0 from LOADING to FULL, Loading Done

r2#sh ipv6 int f0/0
FastEthernet0/0 is up, line protocol is up
  IPv6 is enabled, link-local address is FE80::C831:23FF:FE41:8
  No Virtual link-local address(es):
  No global unicast address is configured
  Joined group address(es):
    FF02::1
    FF02::2
    FF02::5
    FF02::6
    FF02::1:FF41:8

r3#sh ipv6 int f0/0
FastEthernet0/0 is up, line protocol is up
  IPv6 is enabled, link-local address is FE80::C832:23FF:FE41:8
  No Virtual link-local address(es):
  No global unicast address is configured
  Joined group address(es):
    FF02::1
    FF02::2
    FF02::5
    FF02::6
    FF02::1:FF41:8

note when a unicast address is added to both sides...

r2#sh run int f0/0
Building configuration...

Current configuration : 137 bytes
!
interface FastEthernet0/0
 no ip address
 speed auto
 duplex auto
 ipv6 address AAAA::/64 eui-64
 ipv6 enable
 ipv6 ospf 1 area 0

r3#sh ipv6 int f0/0
FastEthernet0/0 is up, line protocol is up
  IPv6 is enabled, link-local address is FE80::C832:23FF:FE41:8
  No Virtual link-local address(es):
  Global unicast address(es):
    AAAA::C832:23FF:FE41:8, subnet is AAAA::/64 [EUI]

global unicast addresses are generated...

we've got choices here...

http://fengnet.com/book/cisco.ios.cookbook.2nd/I_0596527225_CHP_25_SECT_2.html