To use SLAAC on an interface:
Ensure at least one of the routers has an IPv6 address already configured:
R3#conf t Enter configuration commands, one per line. End with CNTL/Z. R3(config)#ipv6 unicast-routing R3(config)#int g1/0 R3(config-if)#ipv6 add 2001:db8::1/64 R3(config-if)#no shutdown R3(config-if)#^Z R3# *Aug 28 10:43:14.631: %SYS-5-CONFIG_I: Configured from console by console
On the other router:
R4#conf t Enter configuration commands, one per line. End with CNTL/Z. R4(config)#ipv6 unicast-routing R4(config)#int g1/0 R4(config-if)#ipv6 address autoconfig R4(config-if)#no shutdown R4(config-if)#^Z R4#
To verify:
R4#show ipv6 int g1/0 GigabitEthernet1/0 is up, line protocol is up IPv6 is enabled, link-local address is FE80::C804:2CFF:FEB4:1C No Virtual link-local address(es): Stateless address autoconfig enabled Global unicast address(es): 2001:DB8::C804:2CFF:FEB4:1C, subnet is 2001:DB8::/64 [EUI/CAL/PRE] valid lifetime 2591921 preferred lifetime 604721 Joined group address(es): FF02::1 FF02::2 FF02::1:FFB4:1C 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 30000 milliseconds (using 26456) 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. R4#