Typical Application - Interface Backup Via Policy-Based Routing - Avaya G450 Manual

Configuring WAN interfaces
Typical application – interface backup via policy-based routing
In the previous typical application (see
interface on page 309), the backup interface command is used to specify a backup
interface. This typical application illustrates an alternative to the backup interface
command, using policy-based routing (PBR) which configures a routing scheme for specified
traffic based on configured characteristics of the traffic. Thus, PBR can be used in combination
with object tracking to configure a backup mechanism for interfaces.
For an example that uses policy-based routing as an alternative to the backup interface
command, replace the last four lines of the previous typical application with the example below.
The example creates a next hop list that sends the specified traffic to the WAN FastEthernet
interface, which is running PPPoE encapsulation. If the WAN FastEthernet interface becomes
unavailable, the next hop list routes the traffic to the Serial interface 3/1:1. PBR list 801 is
created and assigned to interface VLAN 1, so that traffic defined in PBR list 801 passing
through interface VLAN 1 is routed according to the next hop list.
Note:
You can define a static route over the WAN FastEthernet interface running DHCP
Note:
client. In such a case, the static route uses as the next hop the default router
learned from the DHCP server. This is useful for GRE tunnels which are defined
over the WAN Fast Ethernet running DHCP client. It is necessary to define static
routes in order to prevent loops. Therefore, the IP route command allows
configuration of static routes over WAN Fast Ethernet running DHCP client.
312 Administration for the Avaya G450 Media Gateway
Typical application – backup for a WAN FastEthernet