Hi,
Based on my test, in Windows Server 2012, DHCPv6 Stateless mode is disabled by default. If we want to enable it, we need to manually configure DHCPv6 Server Options 00023 DNS Recursive Name Server IPv6 Address List and 00024 Domain Search List.
Also, due to the prefix length for an IPv6 subnet will always be /64, no more, no less, when we create scopes in DHCPv6 Server, we cannot or there is no need to change the default prefix length.
Regarding the default gateway, DHCPv6 does not have the similar Server/Scop Options: 003 Router as DHCPv4, IPv6 Default Gateway is based on Router Advertisements, however, if we would like to configure it for IPv6 Clients, we need to manually configure it via
Netsh command or GUI. Or, we can refer to
Internet-Draft: Default Router and Prefix Advertisement Options for DHCPv6.
In addition, we can address IPv6 related questions in
IPv6 forum for better assistance.
More information:
Reserved IPv6 Subnet Anycast Addresses
IPv6 Addressing (TechRef)
DHCPv6 - Understanding
of address configuration in automatic mode and installation of DHCPv6 Server
IPv6 Router Advertisements (Windows)
Hope this helps.
Jeremy Wu
TechNet Community Support
