3Com Switch 7750 Configuration Guide Guide

640 CHAPTER 59: MIRRORING CONFIGURATION
There are three types of switches with the RSPAN enabled.
■ Source switch: The switch to which the monitored port belongs. The source
switch copies the mirrored traffic flows to the remote-probe VLAN, and then
through Layer 2 forwarding, the mirrored flows are sent to an intermediate
switch or destination switch.
■ Intermediate switch: Switches between the source switch and destination
switch on the network. An intermediate switch forwards mirrored flows to the
next intermediate switch or the destination switch. Circumstances can occur
where no intermediate switch is present, if a direct connection exists between
the source and destination switches.
■ Destination switch: The switch to which the destination port for remote
mirroring belongs. It forwards mirrored flows it received from the remote-probe
VLAN to the monitoring device through the destination port.
Table 508 describes how the ports on various switches are involved in the
mirroring operation.
Tabl e 508 Ports involved in the mirroring operation
Switch Ports involved Function
Source switch
Source port
Port to be mirrored; copy user
data packets to the specified
reflector port through local
port mirroring. There can be
more than one source port.
Reflector port
Receive user data packets that
are mirrored on a local port.
Relay port
Send mirrored packets to the
intermediate switch or the
destination switch.
You must set the port as a
trunk port and specify the
port to permit packets of
remote-probe VLANs.
Intermediate switch Relay port
Send mirrored packets to the
destination switch.
Two relay ports are necessary
for the intermediate switch to
be connected to devices that
are connected to the source
switch and the destination
switch.
You must set the port as a
trunk port and specify the
port to permit packets of
remote-probe VLANs.
Destination switch
Relay port
Receive remote mirrored
packets.
You must set the port as a
trunk port and specify the
port to permit packets of
remote-probe VLANs.
Destination port
Monitor remote mirrored
packets