DGS-3100 Series Gigabit Stackable Managed Switch User Manual 
 
72 
Configuring Port Mirroring  
Switches inherently forward frames to relevant ports only. This creates difficulty when traffic needs to be monitored, either 
for information gathering (such as statistical analysis, security traces, etc.) or for troubleshooting higher-layer protocol 
operation. The device supports up to 8 source ports. 
To enable the use of traffic analysis and monitoring devices, it is recommended enabling the user to specify that a desired 
‘target’ port receives a copy of all traffic passing through a designated ‘source’ port. 
In order to activate Port Mirroring, the target port must belong to the default VLAN. 
 
1.  Click L2 Features > Port Mirroring. The 
Port Mirroring Page opens: 
 
Figure 3–13. Port Mirroring Page 
The 
Port Mirroring Page contains the following fields: 
Field  Description 
Status 
Enables or disables target port setting. The default is Disabled. 
Unit 
Defines the unit number. 
Target Port 
Defines the target port. 
Source Port 
Displays the Sniffer Mode and the source port. 
Source Port Setting 
Field  Description 
Unit 
Selects the Unit to be displayed. 
Tx 
Indicates the transmit stream of data on the port. 
Rx 
Indicates the receive stream of data on the port. 
Both 
Defines the port mirroring on both receiving and transmitting ports.