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| 9.2 |  | RSPAN |
| 9.2.2 |  | RSPAN reflector ports |

Reflector ports are used as a mechanism to copy monitored packets onto an RSPAN VLAN. The reflector port only forwards the traffic from the RSPAN source session with which it is affiliated. Any device connected to a port set as a reflector port loses connectivity until the RSPAN source session is disabled.

The reflector port has these characteristics:

- It is a port set to loopback.
- It cannot be an EtherChannel group, it does not trunk, and it cannot do protocol filtering.
- It can be a physical port that is assigned to an EtherChannel group, even if the EtherChannel group is specified as a SPAN source. The port is removed from the group while it is configured as a reflector port.
- A port used as a reflector port cannot be a SPAN source or destination port, nor can a port be a reflector port for more than one session at a time.
- It is invisible to all VLANs.
- The native VLAN for looped-back traffic on a reflector port is the RSPAN VLAN.
- The reflector port loops back untagged traffic to the switch. The traffic is then placed on the RSPAN VLAN and flooded to any trunk ports that carry the RSPAN VLAN.
- Spanning tree is automatically disabled on a reflector port.
- If the bandwidth of the reflector port is not sufficient to handle the traffic from the corresponding source ports, the excess packets are dropped. A 10/100 port reflects at 100 Mbps. A Gigabit port reflects at 1 Gbps.

The configuration command necessary to assign an existing port as a reflector port is:

> Switch(config)#monitor session session_number destination remote vlan vlan_id reflector-port interface

Where session_number represents the RSPAN monitoring session, vlan_id identifies the unique RSPAN VLAN and interface specifies the interface that will flood the RSPAN traffic to the RSPAN VLAN.