Behavior of a Port-Mirroring Filter Applied to an Aggregated Ethernet Interface

You can apply a Layer 2 port-mirroring firewall filter to an aggregated Ethernet interface to configure port-mirroring at the parent interface. However, if any child interfaces are bound to different Layer 2 port-mirroring instances, packets received at the child interfaces will be mirrored to the destinations specified by their respective port-mirroring instances. Thus, multiple child interfaces can mirror packets to multiple destinations.

For example, suppose the parent aggregated Ethernet interface instance ae0 has two child interfaces:

• xe-2/0/0
• xe-3/1/2

Also suppose that these child interfaces on ae0 are each bound to a different Layer 2 port-mirroring instance:

• pmi-A—Layer 2 port-mirroring instance bound to child interface xe-2/0/0
• pmi-B—Layer 2 port-mirroring instance bound to child interface xe-3/1/2

If you apply a Layer 2 port-mirroring firewall filter to ae0.0 (logical unit 0 on the aggregated Ethernet interface instance 0). This enables port mirroring on ae0.0, which has the following effect on the processing of traffic received on the child interfaces for which Layer 2 port-mirroring properties are specified:

• The packets received on xe-2/0/0.0 are mirrored to the output interfaces configured in port-mirroring instance pmi-A.
• The packets received on xe-3/1/2.0 are mirrored to the output interfaces configured in port-mirroring instance pmi-B.

Because pmi–A and pmi–B might specify different input packet-sampling properties or mirror destination properties, the packets received on xe-2/0/0.0 and xe-3/1/2.0 can mirror different packet to different destinations.

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