Foundry NetIron M2404C and M2404F Metro Access Switches
Troubleshooting and Monitoring (Rev. 03)
Traffic Monitoring
© 2008 Foundry Networks, Inc.
Page 15 of 55
Traffic Monitoring
Traffic monitoring extends the monitoring capabilities of existing network analyzers into a
switched Ethernet environment. Traffic can be monitored on ports and VLANs by configuring
another port to “mirror” the traffic on the ports or VLANs the user wants to monitor. By attaching
an analyzer to the mirror port, the system administrator can observe the traffic on the monitored
ports and analyze the traffic on the network.
Overview
A local monitor session is an association of a destination port with source ports and source
VLANs. The user configures monitor sessions by using parameters that specify the source of
network traffic to the monitor.
For example, in
Figure 1,
all traffic on ports 1/1/1, 1/1/2, 1/1/3, 1/1/5, 1/1/6 and 1/1/8 is monitored
by the port 1/1/9. A network analyzer on port 1/1/9. receives all network traffic from these ports
without being physically attached to port 1/1/9..
NOTE
The port monitor must be connected to a host (an edge port). Setting a port that is
connected to a network to be a monitor (sniffer) port can cause major network
problems.
Figure 1: Example of Monitor Session Configuration on Interface
9
Figure 2
shows an example of a monitor session. All traffic on VLAN 100 and VLAN 101 (the
source VLANs) is monitored by the port 1/1/4 (the destination port). A network analyzer on port
1/1/4 receives the network traffic on the VLANs.