D-Link NetDefendOS User Manual page 412

• if1_dns6_2 - The second IPv6 DNS address in the DHCP lease.
• if1_net6 - The interface network (requires Router Discovery is enabled).
• if1_gw6 - The gateway (requires Router Discovery is enabled).
The DHCP client mechanism not only creates these objects but also assigns them to the relevant
property in the interface. Using the Router Discovery option is discussed later in this section.
Enabling DHCPv6
Similar to DHCP with IPv4, DHCPv6 is enabled using the Enable DHCPv6 property for a specific
interface. By default, this property is disabled.
In addition, a number of other properties can be optionally specified for an interface:
• Preferred IP
This is a suggestion sent to the DHCPv6 server for what the interface IP should be.
• Preferred Lifetime and Valid Lifetime
These are suggestions sent to the DHCPv6 server for what the lifetimes should be.
• Lease Filter
This a range of acceptable IPv6 addresses that can be assigned to the interface. If the offered
lease does not contain this address, it is rejected.
• Server Filter
This is a range of IPv6 addresses for servers from which NetDefendOS will accept leases.
The Router Discovery Option
An Ethernet configuration object has an additional property called Router Discovery which is
either disabled or enabled.
By default, this option is disabled which means that the DHCPv6 client feature will only set the
IPv6 address for the interface and the IPv6 addresses of DNS servers, while the network address
and the gateway addresses must be set manually by the administrator.
When the Router Discovery option is enabled, a complete set of client addresses will be provided
by the DHCPv6 process including the IPv6 network and the IPv6 gateway address. This is similar
to the standard way that IPv4 functions.
Tip: An ISP will have a correct IPv6 connection method
When connecting to an ISP using IPv6, check with the ISP how NetDefendOS should be
configured. Using the DHCP client with Router Discovery enabled may be required by
the ISP to retrieve the IPv6 address for the ISP's gateway as well as for the IPv6 network.
The Router Discovery option can also be used when automatically configuring the IPv6 address of
the interface, with the DHCP client function disabled. This usage is described in Section 3.2, "IPv6
Support".
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Chapter 5: DHCP Services