Ingress and Egress Multicast Replication using Recycle Replication Model

In ingress and egress replication with recycle port, there are two passes for each multicast packet. In the first pass, each packet is replicated to each egress Packet Forwarding Engine in the system using the Egress Packet Forwarding Engine’s recycle port. In the second pass, packets are replicated to the ports of the egress Packet Forwarding Engine.

With this replication model, replication for the ports of a Packet Forwarding Engine occurs in the same Packet Forwarding Engine. Post replication, multicast packet flows are as good as unicast packet flows. There are no separate queues for multicast traffic. Unicast Traffic is scheduled as usual by getting credit from egress ports.

Recycle port is an internal logical port designed for loopback between egress and ingress pipeline in the system. Recycle port is created during boot time only if the recycle based replication is enabled from CLI. use set ingress-egress-recycle statement at the system packet-forwarding-options mcast-repl-type hierarchy level for ingress and egress multicast replication using Recycle replication model. If you don’t select the replication type, ingress replication (ingress-only) is considered as the default replication type.

The overall Multicast traffic flow towards egress PFE is restricted by recycle port bandwidth. Recycle port bandwidth is fixed with default bandwidth set to 30Gbps.