R1#
interface Ethernet0/1
 no ip address
 half-duplex
 ipv6 address 2005:0:104::/64 eui-64
 ipv6 rip RipR1 enable
!
interface Serial0/1
 no ip address
 ipv6 address 2005:0:102::/64 eui-64
 ipv6 rip RipR1 enable
 clock rate 64000
!
router rip
 version 2
 network 180.40.0.0
 no auto-summary
!
no ip http server
ip classless
!
!
ipv6 router rip RipR1

R2#sh run  int s 1/1
Building configuration...

Current configuration : 102 bytes
!
interface Serial1/1
 no ip address
 ipv6 address 2005:0:102::/64 eui-64
 ipv6 rip RipR2 enable
end

R2#

R4#sh run | b inter
interface Loopback0
 no ip address
 ipv6 address 2000:4:4::4/64
 ipv6 rip RipR4 enable
!
interface FastEthernet0/0
 no ip address
 duplex auto
 speed auto
 ipv6 address 2005:0:104::/64 eui-64
 ipv6 rip RipR4 enable
!