4.3.5. The Ordering parameter
Example 4.3. Creating a Policy-Based Routing table
In this example we create a Policy-based Routing table named "TestPBRTable".
Web Interface
1.
Go to Routing > Routing Tables > Add > RoutingTable
2.
Now enter:
•
Name: TestPBRTable
•
For Ordering select one of:
•
First - the named routing table is consulted first of all. If this lookup fails, the lookup will continue in the
main routing table.
•
Default - the main routing table will be consulted first. If the only match is the default route (0.0.0.0/0),
the named routing table will be consulted. If the lookup in the named routing table fails, the lookup as a
whole is considered to have failed.
•
Only - the named routing table is the only one consulted. If this lookup fails, the lookup will not contin-
ue in the main routing table.
3.
If Remove Interface IP Routes is enabled, the default interface routes are removed, i.e. routes to the core
interface (which are routes to NetDefendOS itself).
4.
Click OK.
Example 4.4. Creating the Route
After defining the routing table "TestPBRTable", we add routes into the table.
Web Interface
1.
Go to Routing > Routing Tables > TestPBRTable > Add > Route
2.
Now enter:
•
Interface: The interface to be routed
•
Network: The network to route
•
Gateway: The gateway to send routed packets to
•
Local IP Address: The IP address specified here will be automatically published on the corresponding in-
terface. This address will also be used as the sender address in ARP queries. If no address is specified,
the firewall's interface IP address will be used.
•
Metric: Specifies the metric for this route. (Mostly used in route fail-over scenarios)
3.
Click OK
Example 4.5. Policy Based Routing Configuration
This example illustrates a multiple ISP scenario which is a common use of Policy-based Routing. The following is
assumed:
•
Each ISP will give you an IP network from its network range. We will assume a 2-ISP scenario, with the net-
work 1.2.3.0/24 belonging to "ISP A" and "2.3.4.0/24" belonging to "ISP B". The ISP gateways are 1.2.3.1 and
2.3.4.1, respectively.
•
All addresses in this scenario are public addresses for the sake of simplicity.
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Chapter 4. Routing