D-Link DFL-260 Product Manual - Page 185

Dynamic Routing Rules, 4.5.4.1. Overview, Note: Linking partitioned backbones

Page 185 highlights

4.5.4. Dynamic Routing Rules Chapter 4. Routing Authentication Use Default For AS Use the values configured in the AS properties page. Note: Linking partitioned backbones If the backbone area is partitioned, a virtual link is used to connect the different parts. In most, simple OSPF scenarios, OSPF VLink objects will not be needed. 4.5.4. Dynamic Routing Rules This section looks at Dynamic Routing Rules which dictate which routes can be exported to an OSPF AS from the local routing tables and which can be imported into the local routing tables from the AS. 4.5.4.1. Overview The Final OSPF Setup Step is Creating Dynamic Routing Rules After the OSPF structure is created, the final step is always to create a Dynamic Routing Rule on each NetDefend Firewall which allows the routing information that the OSPF AS delivers from remote firewalls to be added to the local routing tables. Dynamic routing rules are discussed here in the context of OSPF, but can also be used in other contexts. The Reasons for Dynamic Routing Rules 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 parts of the routing database getting published to other routers. For this reason, Dynamic Routing Rules are used to regulate the flow of routing information. These rules filter 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. Usage with OSPF Dynamic Routing Rules are used with OSPF to achieve the following: • Allowing the import of routes from the OSPF AS into local routing tables. • Allowing the export of routes from a local routing tables to the OSPF AS. • Allowing the export of routes from one OSPF AS to another OSPF AS. Note The last usage of joining asynchronous systems together is rarely encountered except in very large networks. 185

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Authentication
Use Default For AS
Use the values configured in the AS properties page.
Note: Linking partitioned backbones
If the backbone area is partitioned, a virtual link is used to connect the different parts.
In most, simple OSPF scenarios,
OSPF VLink
objects will not be needed.
4.5.4. Dynamic Routing Rules
This section looks at
Dynamic Routing Rules
which dictate which routes can be exported to an
OSPF AS from the local routing tables and which can be imported into the local routing tables from
the AS.
4.5.4.1. Overview
The Final OSPF Setup Step is Creating Dynamic Routing Rules
After the OSPF structure is created, the final step is always to create a
Dynamic Routing Rule
on
each NetDefend Firewall which allows the routing information that the OSPF AS delivers from
remote firewalls to be added to the local routing tables.
Dynamic routing rules are discussed here in the context of OSPF, but can also be used in other
contexts.
The Reasons for Dynamic Routing Rules
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 parts of the routing database getting published to other
routers.
For this reason,
Dynamic Routing Rules
are used to regulate the flow of routing information.
These rules filter 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.
Usage with OSPF
Dynamic Routing Rules are used with OSPF to achieve the following:
Allowing the import of routes from the OSPF AS into local routing tables.
Allowing the export of routes from a local routing tables to the OSPF AS.
Allowing the export of routes from one OSPF AS to another OSPF AS.
Note
The last usage of joining asynchronous systems together is rarely encountered except
in very large networks.
4.5.4. Dynamic Routing Rules
Chapter 4. Routing
185