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

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route in the main routing table for each physical interface. These routes are assigned a default IP
address object in the address book and these IP objects must have their addresses changed to the
appropriate range for traffic to flow.
Note: The metric for default routes is 100
The metric assigned to the default routes automatically created for the physical
interfaces is always 100.
These automatically added routes cannot be removed manually by deleting them one at a time
from a routing table. Instead, the properties of the interface must be selected and the advanced
option Automatically add a route for this interface using the given network must be disabled.
This will remove any route that was added automatically at startup. This option has no other purpose
but to delete the automatically added routes.
The all-nets Route
The most important route that should be defined is the route to all-nets which usually corresponds to
an ISP that provides public Internet access. If using the NetDefendOS setup wizard, this route is also
added automatically.
However, the option also exists for any physical interface to indicate that it should be used for
connection to the Internet. In the Web Interface this is an advanced setting in the Ethernet interface
properties called:
Automatically add a default route for this interface using the given default gateway.
When this option is selected, the appropriate all-nets route is automatically added to the main
routing table for the interface.
Core Routes
NetDefendOS automatically populates the active routing table with Core Routes. These routes are
present for the system to understand where to route traffic that is destined for the system itself.
There is one route added for each interface in the system. In other words, two interfaces named lan
and wan, and with IP addresses 192.168.0.10 and 193.55.66.77, respectively, will result in the
following routes:
Route # Interface Destination Gateway
1 core 192.168.0.10
2 core 193.55.66.77
When the system receives an IP packet whose destination address is one of the interface IPs, the
packet will be routed to the core interface. In other words, it is processed by NetDefendOS itself.
There is also a core route added for all multicast addresses:
Route # Interface Destination Gateway
1 core 224.0.0.0/4
To include the core routes when the active routing table is displayed, it is necessary to explicitly
specify that all routes are to be displayed. This is shown in the example below.
Example 4.2. Displaying the Core Routes
4.2.2. Static Routing Chapter 4. Routing
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