Optional. Used to specify from which subnet prefixes an IPv6 address should be allocated, or to assign valid available IPv6 addresses.
Optional. An available IPv6 address of your subnet from a valid IPv6 prefix on the subnet (otherwise the IP address is automatically assigned).
Optional. Used to disambiguate which subnet prefix should be used to create an IPv6 allocation.
Optional. Used to specify from which subnet prefixes an IPv6 address should be allocated, or to assign valid available IPv6 addresses.