3com 5500G ユーザーズマニュアル

Remote port mirroring does not require the source and destination ports to be on 
the same device. The source and destination ports can be located on multiple 
devices across the network. Therefore, administrators can monitor the traffic on 
remote devices conveniently.

A special VLAN, called remote-probe VLAN, is needed to implement remote port 
mirroring. All mirrored packets are sent from the reflector port of the source 
switch to the monitor port (destination port) of the destination switch through the 
remote-probe VLAN, so that you can monitor packets received on and sent from 
the source switch on the destination switch. Figure 68 illustrates the 
implementation of remote port mirroring.

Figure 68   Remote port mirroring application

 

Switches involved in remote port mirroring play one of the following three roles:

■

Source switch: The monitored port resident switch. It copies traffic to the 
reflector port, which then transmits the traffic to an intermediate switch or the 
destination switch through the remote-probe VLAN.

■

Intermediate switch: Switches between the source switch and the destination 
switch on the network. An intermediate switch forwards mirrored traffic to the 
next intermediate switch or the destination switch through the remote-probe 
VLAN. No intermediate switch is present if the source switch and the 
destination switch are directly connected to each other.

■

Destination switch: The remote mirroring destination port resident switch. It 
forwards mirrored traffic received from the remote-probe VLAN to the 
monitoring device through the destination port.

Reflector Port

Source Port

Trunk Port

Destination Port

Remote-probe VLAN

Intermediate Switch

Source 

Switch

Destination 

Switch