ECMP Support on ICL in Multinode High Availability

Equal-Cost Multi-Path (ECMP) allows the distribution of traffic across multiple paths that have the same cost, thereby increasing throughput and providing path redundancy. In a Multinode High Availability setups, you can use ECMP to enhance the ICL (Interchassis Link) by configuring it to utilize multiple links. This is achieved by enabling ECMP on the ICL, allowing traffic to be distributed across multiple paths, thereby optimizing the performance and redundancy of the ICL. In an MNHA configuration, where the reliability and efficiency of network traffic are paramount, ECMP ensures that no single path becomes a congestion, and that network resources are utilized effectively.

Configure ICL to Use ECMP

1. For the ICL configuration, follow the standard MNHA ICL setup process. Use the lo0 interface as the local and peer endpoints. See Example: Configure Multinode High Availability in a Layer 3 Network.

2. IEnable the l4-key-ecmp under the [edit security flow] hierarchy on both devices in MNHA setup:

3. Ensure ICL peer reachability through routing protocols or static routes with ECMP policy enabled.

4. Configure load-balancing policies to efficiently distribute traffic across multiple paths.

   • The following configuration snippets set up a static route with two possible next-hop paths for destination 11.0.1.1 and applies per-packet load balancing to distribute traffic evenly across these paths.

   • ECMP load-balancing policy:

5. Use the show route forwarding-table destination command to check if the multiple paths or interfaces for ICL peer are installed in forwarding table due to ECMP configuration.

Check Feature Explorer for support on different platforms.