Enabling Dhcp - D-Link NetDefend DFL-210 User Manual

3.3.2. Ethernet
The names of the Ethernet interfaces are pre-defined by the system, and are mapped to the names of
the physical ports; a system with a wan port will have an Ethernet interface named wan and so on.
The names of the Ethernet interfaces can be changed to better reflect their usage. For instance, if an
interface named dmz is connected to a wireless LAN, it might be convenient to change the interface
name to radio. For maintenance and troubleshooting, it is recommended to tag the corresponding
physical port with the new name.
Ethernet IP Addresses
Each Ethernet interface is required to have an Interface IP Address, which can be either a static
address or an address provided by DHCP. The interface IP address is used as the primary address for
communicating with the system through the specific Ethernet interface.
The standard is to use IP4 Address objects to define the addresses of Ethernet interfaces. Those
objects are normally auto-generated by the system. For more information, please see Section 3.1.5,
"Auto-Generated Address Objects".
In addition to the interface IP address, a Network address is also specified for the Ethernet interface.
The Network address provides information to NetDefendOS about what IP addresses are directly
reachable through the interface, in other words those residing on the same LAN segment as the
interface itself. In the routing table associated with the interface, NetDefendOS will automatically
create a direct route to the specified network over the actual interface.
The Default Gateway
A Default Gateway address can optionally be specified for an Ethernet interface. This setting tells
NetDefendOS how to reach hosts for which no routes exist. In other words, if a Default Gateway
address has been specified, NetDefendOS will automatically create a default route (destination
network all-nets) over the actual interface using the specified gateway. For natural reasons, only one
Ethernet interface at a time can be assigned a default gateway.
Using DHCP on Ethernet Interfaces
NetDefendOS includes a DHCP client for dynamic assignment of address information. The
information that can be set using DHCP includes the IP address of the interface, the local network
that the interface is attached to, and the default gateway.
All addresses received from the DHCP server are assigned to corresponding IP4Address objects. In
this way, dynamically assigned addresses can be used throughout the configuration in the same way
as static addresses. By default, the objects in use are the same ones as defined in Section 3.1.5,
"Auto-Generated Address Objects".
Example 3.10. Enabling DHCP
CLI
Note
The startup process will enumerate all available Ethernet interfaces. Each interface
will be given a name of the form lanN, wanN and dmz, where N represents the number
of the interface if your D-Link Firewall has more than one of these interfaces. In most
of the examples in this guide lan is used for LAN traffic and wan is used for WAN
traffic. If your D-Link Firewall does not have these interfaces, please substitute the
references with the name of your chosen interface.
Tip
Multiple IP addresses can be specified for an Ethernet interface by using the ARP
Publish feature. (For more information, see Section 3.4, "ARP").
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Chapter 3. Fundamentals