ipv6 route ::/0 2001:db8:1234:2::1 2. A floating static default route must use the IPv6 default prefix ::/0 and an administrative distance higher than the current preferred default route. A ::/128 route is a host route to the unspecified address and is not a default route. An administrative distance of 1 would be the normal static-route distance and would not behave as a backup to another static default route. Cisco CCNA 200-301 v1.1 IP Connectivity expects candidates to understand both the IPv6 default route syntax and the purpose of the final distance value. The corrected command uses ipv6 route ::/0 toward 2001:db8:1234:2::1 with a higher administrative distance. That keeps the route out of the routing table while the primary default route is valid and installs it only when the primary route fails.