Virtual Span Sessions; Network Analysis Module - Cisco Nexus 7000 Series Configuration Manual

Virtual SPAN Sessions

Extended SPAN is supported in the egress direction only. In the case of an extended SPAN Rx session, the
exception source configuration will be rejected.
Virtual SPAN Sessions
You can create a virtual SPAN session to monitor multiple VLAN sources and choose only VLANs of
interest to transmit on multiple destination ports. For example, you can configure SPAN on a trunk port and
monitor traffic from different VLANs on different destination ports.
The figure below shows a virtual SPAN configuration. The virtual SPAN session copies traffic from the three
VLANs to the three specified destination ports. You can choose which VLANs to allow on each destination
port to limit the traffic that the device transmits on it. In the figure below, the device transmits packets from
one VLAN at each destination port.
Note Virtual SPAN sessions cause all source packets to be copied to all destinations, whether the packets are
required at the destination or not. VLAN traffic filtering occurs at the egress destination port level.
Figure 5: Virtual SPAN Configuration
For information about configuring a virtual SPAN session see the Configuring a Virtual SPAN Session section.

Network Analysis Module

You can also use the Cisco Network Analysis Module (NAM) to monitor SPAN data sources for application
performance, traffic analysis, and packet header analysis.
To use NAM for monitoring the Cisco Nexus 7000 SPAN data sources, see the Cisco Nexus 7000 Series
Network analysis Module (NAM-NX1) Quick Start Guide.
Cisco Nexus 7000 Series NX-OS System Management Configuration Guide
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Configuring SPAN