D-Link DFL-2500 - Manual (Page 108)

In a dynamic routing environment, it is important for routers to be able to regulate to what extent
they will participate in the routing exchange. It is not feasible to accept or trust all received routing
information, and it might be crucial to avoid that parts of the routing database gets published to
other routers.
For this reason, NetDefendOS provides a Dynamic Routing Policy, which is used to regulate the
flow of dynamic routing information.
A Dynamic Routing Policy rule filters either statically configured or OSPF learned routes according
to parameters like the origin of the routes, destination, metric and so on. The matched routes can be
controlled by actions to be either exported to OSPF processes or to be added to one or more routing
tables.
The most common usages of Dynamic Routing Policy are:
• Importing OSPF routes from an OSPF process into a routing table.
• Exporting routes from a routing table to an OSPF process.
• Exporting routes from one OSPF process to another.
Note
By default, NetDefendOS will not import or export any routes. In other words, for
dynamic routing to be meaningful, it is mandatory to define at least one Dynamic
Routing Policy rule.
Example 4.6. Importing Routes from an OSPF AS into the Main Routing Table
In this example, the routes received using OSPF will be added into the main routing table. First of all a Dynamic
Routing Policy filter needs to be created. The filter needs to have a name, in this example ImportOSPFRoutes is
used, as it explains what the filter does.
The filter must also specify from what OSPF AS the routes should be imported. In this example, a pre-configured
OSPF AS named as0 is used.
Depending on how your routing topology looks like you might want to just import certain routes using the
Destination Interface/Destination Network filters, but in this scenario all routes that are within the all-nets network
(which is the same as specifiying the IP address 0.0.0.0/0) are allowed.
CLI
gw-world:/> add DynamicRoutingRule OSPFProcess=as0 Name=ImportOSPFRoutes
DestinationNetworkExactly=all-nets
Web Interface
1. Go to Routing > Dynamic Routing Rules > Add > Dynamic routing policy rule
2. Specify a suitable name for the filter, in this case ImportOSPFRoutes
3. In the Select OSPF Process, select as0
4. Choose all-nets in the ...Exactly Matches dropdown control
5. Click OK
The next step is to create a Dynamic Routing Action that will do the actual importing of the routes into a routing
table. Specify the destination routing table that the routes should be added to, in this case main.
CLI
gw-world:/> cc DynamicRoutingRule ImportOSPFRoutes
4.4.3. Dynamic Routing Policy Chapter 4. Routing
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