Local Span, Rspan, And Erspan Sources; Local Span, Rspan, And Erspan Destination Ports - Cisco WS-SUP32-GE-3B - Supervisor Engine 32 Software Configuration Manual

Chapter 48 Configuring Local SPAN, RSPAN, and ERSPAN
packet was Layer 2 switched from s1 to s2, both SPAN packets would be the same. If the packet was
Layer 3 switched from s1 to s2, the Layer 3 rewrite would alter the source and destination Layer 2
addresses, in which case the SPAN packets would be different.

Local SPAN, RSPAN, and ERSPAN Sources

These sections describe local SPAN, RSPAN, and ERSPAN sources:
•
•
Source Ports
A source port is a port monitored for traffic analysis. You can configure both switched and routed ports
as SPAN source ports. SPAN can monitor one or more source ports in a single SPAN session. You can
configure source ports in any VLAN. Trunk ports can be configured as source ports and mixed with
nontrunk source ports. SPAN does not copy the encapsulation from a source trunk port.
Source VLANs
A source VLAN is a VLAN monitored for traffic analysis. VLAN-based SPAN (VSPAN) uses a VLAN
as the SPAN source. All the ports in the source VLANs become source ports.

Local SPAN, RSPAN, and ERSPAN Destination Ports

A destination port is a Layer 2 or Layer 3 LAN port to which local SPAN, RSPAN, or ERSPAN sends
traffic for analysis.
When you configure a port as a destination port, it can no longer receive any traffic. When you configure
a port as a destination port, the port is dedicated for use only by the SPAN feature. A SPAN destination
port does not forward any traffic except that required for the SPAN session.
You can configure trunk ports as destination ports, which allows destination trunk ports to transmit
encapsulated traffic. For local SPAN, you can configure per-VLAN filtering on destination trunk ports
using allowed VLAN lists (see the
page
OL-11439-03
Source Ports, page 48-5
Source VLANs, page 48-5
48-21).
Catalyst Supervisor Engine 32 PISA Cisco IOS Software Configuration Guide, Release 12.2ZY
Understanding How Local SPAN, RSPAN, and ERSPAN Work
"Configuring Destination Trunk Port VLAN Filtering" section on
48-5