D-Link DGS-3120-24TC Product Manual - Page 302

xStack® DGS-3120 Series Managed Switch Web UI Reference Guide Mirror 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. This is useful for network monitoring and troubleshooting purposes. Port Mirror Settings To view this window, click Monitoring > Mirror > Port Mirror Settings as shown below: Figure 11-16 Port Mirror Settings window The fields that can be configured are described below: Parameter Description State Click the radio buttons to enable or disable the Port Mirroring feature. Target Port Use the drop-down menu to select the Target Port used for Port Mirroring. Unit Select the unit you want to configure. TX (Egress) Click the radio buttons to select whether the port should include outgoing traffic. RX (Ingress) Click the radio buttons to select whether the port should include incoming traffic. Both Click the radio buttons to select whether the port should include both incoming and outgoing traffic. None Click the radio buttons to select whether the port should not include any traffic. Click the Apply button to accept the changes made. 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. Please note a target port and a source port cannot be the same port. RSPAN Settings This page controls the RSPAN function. The purpose of the RSPAN function is to mirror packets to a remote switch. A packet travels from the switch where the monitored packet is received, passing through the intermediate switch, and then to the switch where the sniffer is attached. The first switch is also named the source switch. To make the RSPAN function work, the RSPAN VLAN source setting must be configured on the source switch. For the intermediate and the last switch, the RSPAN VLAN redirect setting must be configured. 294