Starting in Junos OS Release 20.1R1, on MX Series MPCs, adaptive load balancing (ALB) for aggregated Ethernet bundles evenly redistributes the traffic load across multiple ingress Packet Forwarding Engines on the same line card, thus providing flexibility and redundancy. In earlier releases, ALB evenly redistributes traffic across all ingress traffic on a single Packet Forwarding Engine only. ALB is disabled by default.