IPv6 EUI-64 explained

Lessons Discussion
10

Hi Diana,

Here’s an example:

R1#show ipv6 interface GigabitEthernet 0/1
GigabitEthernet0/1 is up, line protocol is up
  IPv6 is enabled, link-local address is FE80::F816:3EFF:FEE6:7777

That’s the IPv6 link-local address that uses EUI-64. You can configure it manually if you want:

R1(config)#int gi0/1                                                      
R1(config-if)#ipv6 address FE80:1111:1111:1111:ABCD:ABCD:ABCD:ABCD link-local

R1#show ipv6 interface GigabitEthernet 0/1 | include FE80
  IPv6 is enabled, link-local address is FE80:1111:1111:1111:ABCD:ABCD:ABCD:ABCD

Here’s a global unicast address with EUI-64:

R1(config-if)#ipv6 address 2001:1111:1111:1111::/64 eui-64

R1#show ipv6 interface GigabitEthernet 0/1 | include 2001:
    2001:1111:1111:1111:F816:3EFF:FEE6:7777, subnet is 2001:1111:1111:1111::/64

If you don’t want to use EUI-64 then you can configure global unicast addresses yourself:

R1(config-if)#ipv6 address 2001:1111:1111:1111:ABCD:ABCD:ABCD:ABCD/64

R1#show ipv6 interface GigabitEthernet 0/1 | include ABCD 
    2001:1111:1111:1111:ABCD:ABCD:ABCD:ABCD, subnet is 2001:1111:1111:1111::/64 
    FF02::1:FFCD:ABCD

That’s it. Hope this helps.

Rene