Mirroring enables the SmartNIC to deliver a copy of a frame to a queue in the host while simultaneously processing and transmitting the frame on a specified port.
Analyzing frames without interrupting processing
This DPDK testpmd command creates a flow rule that matches frames with
the destination IP address 21.22.23.24.
flow create 0 group 0 pattern ipv4 dst is 21.22.23.24 / end actions queue index 0 / port_id id 1 / endWhen a frame matches this pattern, it is delivered to queue 0 while the same frame is transmitted on port 1. Frames are delivered to the host without any modifications. Mirroring, therefore, allows the application in the host to analyze received frames without affecting frame processing in the SmartNIC.