For IPv6 peers, the route refresh capability is enabled by default, and no address family is enabled by default. You must enable a common set of capabilities on the local and neighbor peers before peering can be established. For IPv6 capability negotiation, IPv6 peering is set to idle if no common address families are negotiated. IPv6 BGP peering supports only the IPv6 unicast and IPv6 multicast address families; IPv4 address families are not supported.