Classifier policies and mirroring sessions

Network traffic can be mirrored to a destination interface in two ways:

  • Using a mirroring session alone.

  • Using Classifier Policies with mirror actions in conjunction with a mirroring session.

Basic mirroring sessions provide coarse control over the type of traffic mirrored from a source: all received, all transmitted, or both. However, a traffic class within a Classifier Policy applied to a source can provide much finer grained control of mirrored traffic. For example, a policy can match on many different aspects of the Ethernet or IPv4 or IPv6 header information in each frame or packet received or transmitted on an interface.

The steps to configure a policy and class with a mirror action are the following:

  1. Configuring a mirroring session with a destination interface.

  2. Enabling the mirroring session.

  3. Configuring the Classifier Policy, specifying the mirroring session ID in the mirror action.