Port Mirroring - D-Link DES-3225G Series User Manual

24-port NWay Ethernet Switch User's Guide

Port Mirroring

The Switch allows you to copy frames transmitted and received on a port and redirect the copies to another
port. You can attach a monitoring device to the mirrored port, such as a sniffer or an RMON probe, to view
details about the packets passing through the first port.
To configure a mirror port, select Enabled from the Port mirroring in pull-down list. In the next field, select
the Source Port from where you want to copy frames. In the last field, select the Target Port, which
receives the copies from the source port. This is the port where you will connect a monitoring/troubleshooting
device such as a sniffer or an RMON probe. Click Apply to let the changes take effect.
Note: You cannot mirror a fast port onto a slower port. For example, if you try to mirror the traffic from
a 100 Mbps port onto a 10 Mbps port, this can cause throughput problems. The port you are
copying frames from should always support an equal or lower speed than the port to which you
are sending the copies. Also, the target port for the mirroring cannot be a member of a trunk
group.
Web-Based Network Management
Figure 7-3. Port Mirroring window
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