15.3(2)TからHSRPのVIPとしてGUAがサポートされたようなので試してみました。
CISCO892-K9 IOS 15.3(1)Tの場合 Router(config)#interface vlan 15 Router(config-if)#standby ? Router(config-if)#standby ipv6 ? X:X:X:X::X IPv6 link-local address autoconfig Obtain address using autoconfiguration CISCO892-K9 IOS 15.3(2)Tの場合 Router(config)#interface vlan 15 Router(config-if)#standby 0 ipv6 ? X:X:X:X::X IPv6 link-local address X:X:X:X::X/<0-128> IPv6 prefix autoconfig Obtain address using autoconfiguration Router(config-if)#standby 0 ipv6 2001:db8::1/64 Router(config-if)#end Router#show standby brief all Load for five secs: 49%/0%; one minute: 24%; five minutes: 10% Time source is NTP, 23:23:14.015 JST Mon May 13 2013 P indicates configured to preempt. | Interface Grp Pri P State Active Standby Virtual IP Vl15 0 100 Init unknown unknown FE80::5:73FF:FEA0:0 (impl auto EUI64) Vl15 0 100 Init unknown unknown 2001:DB8::1/64 Router#