20.1.1 Overview

Policy-based mirroring is the ability to copy a specific flow from an incoming frame and send it to a specified interface. Copying a frame is called mirroring, and the copied frame is called mirroring frame. By using this function, traffic can be monitored and analyzed by receiving mirroring frames for each flow with an analyzer, etc.

The following figure shows the mirroring operation for received frames.

Figure 20-1: Mirroring received frames

As shown in the figure, an interface that monitors traffic is called a monitor port, and an interface to which mirroring frames are sent is called a mirror port.

With policy-based mirroring on the Switch, a detailed frame can be identified by flow detection. You can also mirror multiple mirror ports at the same time.