Assigning a Policy Route-Map to an Interface

Route-map filtering does not occur until the configured route-map is assigned to an interface. Once assigned to an interface the route-map is operational.

On the 7100-Series, next hop load-policy is hard coded to first-available next hop from the list of next hops.

On the S- and K-Series, next hop load-policy and priority can also be configured at the interface level. Load-policy determines the load balancing algorithm that will be used in the next hop selection process. The three configurable options are:

• first-available - The first available next hop from the list of next hops is used (default)
• round-robin - The selection process moves through the list in a sequential circular fashion repeating the sequence when it comes to the end of the list
• ip-hash - The selection is based on an exclusive-or (XOR) hash of the IP source address, IP destination address, or both

On the 7100-Series, priority is hard coded to prioritize use of the priority-based routing by using the priority-based routing next hop, but if it is unavailable, the route table is used.

On the S- and K-Series, priority allows the user to specify whether the route-map lookup or the route table lookup will have priority in the next hop selection process as follows:

• only - Uses the priority based routing next hop and drops the packet if the priority based routing next hop is not available
• first - Uses priority based routing next hop or uses the route table next hop if the priority based next hop is not available
• last - Uses the route table if the route exists there, otherwise the priority based routing next hop is used

Use the ip policy route-map command in interface configuration command mode to assign a route-map to an interface.

On the S- and K-Series, use the ip policy load-policy command in interface configuration command mode to determine the load balancing algorithm that will be used in the next hop selection process.

On the S- and K-Series, use the ip policy priority command in interface configuration command mode to specify whether the route-map lookup or route table lookup will determine the next hop for this route.