Routes can be explicitly specified for advertisement by BGP.
device# configure terminal
device(config)# router bgp
device(config-bgp-router)# neighbor fe80:4398:ab30:45de::1 remote-as 1001
device(config-bgp-router)# address-family ipv6 unicast
device(config-bgp-ipv6u)# network 2001:db8::/32
The following example imports the 2001:db8::/32 prefix in to the BGP4+ database for advertising.
device# configure terminal device(config)# router bgp device(config-bgp-router)# neighbor fe80:4398:ab30:45de::1 remote-as 1001 device(config-bgp-router)# address-family ipv6 unicast device(config-bgp-ipv6u)# network 2001:db8::/32