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

3.3.2. Ethernet Interfaces
As explained next, this way of changing the IP address is not recommended.
• Instead, the ip_lan object in the NetDefendOS Address Book should be assigned the new
address since it is this object that is used by many other NetDefendOS objects such as IP rules.
The CLI command to do this would be:
gw-world:/> set Address IP4Address ip_lan Address=10.1.1.2
This same operation could also be done through the Web Interface.
A summary of CLI commands that can be used with Ethernet interfaces can be found in
Section 3.3.2.1, "Useful CLI Commands for Ethernet Interfaces".
Network Addresses
In addition to the interface IP address, a Network address is also specified for an 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.
Specifying a Default Gateway
A Default Gateway address can optionally be specified for an Ethernet interface. This is a normally
the address of a router and very often the router which acts as the gateway to the Internet.
Normally, only one default all-nets route to the default gateway needs to exist in the routing table.
Using DHCP on Ethernet Interfaces
NetDefendOS includes a DHCP client feature 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".
The enabling of DHCP on an interface is an option in the properties of an interface and can be
enabled or disabled by the administrator. By default, it is disabled. If the interface is being used for
connection to the public Internet via an ISP using a fixed IP address for the interface then DHCP
shouldn't be used.
Example 3.10. Enabling DHCP
Command-Line Interface
gw-world:/> set Interface Ethernet wan DHCPEnabled=Yes
Note: A gateway IP cannot be deleted with DHCP enabled
If DHCP is enabled for a given Ethernet interface then any gateway IP address that is
defined for that interface cannot be deleted. To remove the gateway address, the
DHCP option must be first disabled.
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Chapter 3. Fundamentals