Routing tables

The RouteTable statement can include the following items:

• A set of static routes (both replaceable and non-replaceable static routes are supported)
• A set of dynamic routing parameters that are used for the following purposes:
  • To control the scope of dynamic routes that OMPROUTE computes
  • For IPv6 only, to control the scope of router advertisement routes added to the table
• A dynamic XCF routes indicator

A static route is included by using the Route parameter of the RouteTable statement. A dynamic routing parameter is included by using the DynamicRoutingParms parameter of the RouteTable statement. A dynamic routing parameter consists of an interface, and optionally a next-hop router.

OMPROUTE adds dynamic routes to a policy-based route table only if the interfaces that the routes use are included in the dynamic routing parameters for that table. If a next-hop router is specified with an interface, dynamic indirect routes that use the specified interface are added only if they also use the specified next-hop router.

For IPv6, router advertisement routes are added to a policy-based route table only if the interface that received the router advertisement is included in the dynamic routing parameters for that table. If a next-hop router is specified with an interface, indirect router advertisement routes that use the specified interface are added only if the router advertisement was sent by the specified next-hop router.

Including only static routes, only dynamic routing parameters, or both in a RouteTable statement produces the following results:

• If only static routes are included, the static routes are added to the policy-based route table, but no dynamic routes are added to the table by OMPROUTE and no IPv6 router advertisement routes are added to the table.
• If only dynamic routing parameters are included, dynamic routes are added to the policy-based route table by OMPROUTE and IPv6 router advertisement routes are added to the table based on received router advertisements, but no static routes are added to the table.
• If both static routes and dynamic routing parameters are included, the static routes are added to the policy-based route table. OMPROUTE updates the table with the appropriate dynamic routes, and IPv6 router advertisement routes are added to the table based on received router advertisements.

A dynamic route that is added to a policy-based route table by OMPROUTE is the best route that is known by OMPROUTE to that destination. The calculation of the best route is based on the current network topology. The best route might be a route that is learned from the OSPF protocol or from the RIP protocol, depending on the OMPROUTE configuration. For a description of these protocols, see IPv4 dynamic routing using OMPROUTE and IPv6 dynamic routing using OMPROUTE. When OMPROUTE is computing the best routes for a policy-based route table, it considers only routes that adhere to the dynamic routing parameters configured on the RouteTable statement as described.

If DynamicXCFRoutes Yes is specified on the RouteTable statement and IPCONFIG DYNAMICXCF is specified in the TCP/IP profile, direct host routes to IPv4 dynamic XCF addresses on other TCP/IP stacks are added to the route table when the IPv4 dynamic XCF links to those stacks are active. If DynamicXCFRoutes6 Yes is specified on the RouteTable statement and IPCONFIG6 DYNAMICXCF is specified in the TCP/IP profile, direct host routes to IPv6 dynamic XCF addresses on other TCP/IP stacks are added to the route table when the IPv6 dynamic XCF links to those stacks are active. These same routes are automatically generated in the main route table when dynamic XCF links are active. For information about the dynamic XCF function and the definitions that are automatically generated when IPCONFIG DYNAMICXCF or IPCONFIG6 DYNAMICXCF is specified in the TCP/IP profile, see Dynamic XCF.

After a new routing policy is installed in the TCP/IP stack, traffic is mapped by using the new policy, even for existing connections.