anchor.diff:            "IPv6ProxyNDP"
             "IPv6ProxyNDPAddress"
             "IPv6PrefixDelegation"
  +          "DHCPv6PrefixDelegation"
             "IPv6MTUBytes"
             "Bridge"
             "Bond"
  
positive.code:       description = ''
          Each attribute in this set specifies an option in the
          <literal>[DHCPv6]</literal> section of the unit.  See
          <citerefentry><refentrytitle>systemd.network</refentrytitle>
          <manvolnum>5</manvolnum></citerefentry> for details.
        '';
  
negative.code:         (assertRange "SendOption" 1 65536)
        ];
  
        sectionDHCPv6PrefixDelegation = checkUnitConfig "DHCPv6PrefixDelegation" [
          (assertOnlyFields [
            "SubnetId"
            "Announce"
            "Assign"
            "Token"
          ])
          (assertValueOneOf "Announce" boolValues)
          (assertValueOneOf "Assign" boolValues)
        ];
  
        sectionDHCPServer = checkUnitConfig "DHCPServer" [
          (assertOnlyFields [
            "PoolOffset"
  