Accton Technology 4508, CheetahSwitch Workgroup Management Guide Using a Mirror Port for Analysis

Management Guide

Using a Mirror Port for Analysis

You can mirror traffic from any source port to a target port for real-time analysis. You can then attach a logic analyzer or RMON probe to the target port and study the traffic crossing the source port in a completely unobtrusive manner. When mirroring port traffic, note that the target port must be included in the same VLAN as the source port. (See Configuring Virtual LANs on page 2-41.)

You can use the Mirror Port Configuration screen to designate a single port pair for mirroring as shown below:

CheetahSwitch Workgroup - 4508
Mirror Port Configuration
Analyzer Port	: Port 0
Monitored Port	: Port 0
Analyzer Port Status : DISABLED
<APPLY>	<OK>	<CANCEL>
Use <TAB> or arrow keys to move, other keys to make changes.

Parameter	Description
Mirror Source Port	The port whose traffic will be monitored.
Mirror Target Port	The port that will “duplicate” or “mirror” all the traffic happening on
	the monitored port.
Status	Enables or disables the mirror function.
IGMP Multicast Filtering

Multicasting is used to support real-time applications such as video conferencing or streaming audio. A multicast server does not have to establish a separate connection with each client. It merely broadcasts its service to the network, and any hosts which want to receive the multicast register with their local multicast switch/router. Although this approach reduces the network overhead required by a multicast server, the broadcast traffic must be carefully pruned at every multicast switch/router it passes through to ensure that traffic is only passed on the hosts which subscribed to this service.

This switch uses IGMP (Internet Group Management Protocol) to query for any attached hosts who want to receive a specific multicast service. The switch looks up the IP Multicast Group used for this service and adds any port which received a similar request to that group. It then propagates the service request on to any neighboring multicast switch/router to ensure that it will continue to receive the multicast service. (For more information, see “IGMP Snooping and IP Multicast Filtering” in Chapter 4.)

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