Dear Cisco Community,
I’m facing a strange (?) behavior (IOS 15.2-4 version) with LLA / GUA IPv6 address configuration. In brief : a LLA (Interface ID EUI-64) then a GUA (EUI-64 Interface ID) are configured on an Interface. Then, if I configure a manual LLA (not EUI-64), the GUA (Interface ID) is automaticaly modified with manual Interface ID of the LLA. >> Did I miss something in IPv6 understanding / configuration ?
Here are the commands :
R1(config-if)#ipv6 enable // LLA with IID EUI-64
R1(config-if)#do show ipv6 int brief GigabitEthernet1/0
FE80::C803:1CFF:FE54:1C
R1(config-if)#ipv6 address 2008:ABCD:1::/64 eui-64 // GUA with IID EUI-64
R1(config-if)#do show ipv6 int brief GigabitEthernet1/0
FE80::C803:1CFF:FE54:1C
2008:ABCD:1:0:C803:1CFF:FE54:1C
R1(config-if)#ipv6 address fe80:FEFE:1::1 link-local // LLA with manual IID
R1(config-if)#do show ipv6 int brief GigabitEthernet1/0
FE80:FEFE:1::1
2008:ABCD:1::1 // GUA Interface ID is automatically modified with LLA manual IID
Thanks to all,
Best regards
