D-Link DFL-1600 - Security Appliance, Руководство пользователя

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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”.
By default, DHCP is disabled on Ethernet interfaces. If the interface is being used for connection
to the public Internet via an ISP using fixed IP addresses then DHCP shouldn't be used.
DNS server addresses received through DHCP on an interface named <interface-name> will be
allocated to NetDefendOS address objects with the names <interface-name>_dns1 and
<interface-name>_dns2.
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.
If DHCP is enabled then there is a set of interface specific advanced settings:
i. A preferred IP address can be requested.
ii. A preferred lease time can be requested.
iii. Static routes can be sent from the DHCP server.
iv. Do not allow IP address collisions with static routes.
v. Do not allow network collisions with static routes.
vi. Specify an allowed IP address for the DHCP lease.
vii. Specify an address range for DHCP servers from which leases will be accepted.
• DHCP Hostname
In some, infrequent cases a DHCP server may require a hostname to be sent by the DHCP client.
• Enable Transparent Mode
The recommended way to enable Transparent Mode is to add switch routes, as described in
Section 4.7, “Transparent Mode”. An alternative method is to enable transparent mode directly
on an interface with this option.
When enabled, default switch routes are automatically added to the routing table for the
interface and any corresponding non-switch routes are automatically removed.
• Hardware Settings
In some circumstances it may be necessary to change hardware settings for an interface. The
available options are:
i. The speed of the link can be set. Usually this is best left as Auto.
ii. The MAC address can be set if it needs to be different to the MAC address inbuilt into the
hardware. Some ISP connections might require this.
• Virtual Routing
To implement virtual routing where the routes related to different interfaces are kept in separate
routing table, there are a number of options:
3.3.2. Ethernet Interfaces Chapter 3. Fundamentals
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