Cisco Catalyst 4500 Series Software Configuration Guide

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Catalyst 4500 Series Switch, Cisco IOS Software Configuration Guide - Cisco IOS XE 3.9.xE and IOS 15.2(5)Ex
Chapter 67 Configuring ERSPAN
Information About ERSPAN
ERSPAN supports encapsulated packets of up to 9180 bytes. ERSPAN consists of an ERSPAN source
session, routable ERSPAN GRE-encapsulated traffic, and an ERSPAN destination session.
ERSPAN consists of an ERSPAN source session, routable ERSPAN GRE-encapsulated traffic, and an
ERSPAN destination session. You can configure an ERSPAN source session, an ERSPAN destination
session, or both on a device. A device on which only an ERSPAN source session is configured is called
an ERSPAN source device, and a device on which only an ERSPAN destination session is configured is
called an ERSPAN termination device. A device can act as both; an ERSPAN source device and a
termination device.
Note Catalyst 4500 series switches do not support ERSAPN destination type/session.
For a source port or a source VLAN, the ERSPAN can monitor the ingress, egress, or both ingress and
egress traffic. By default, ERSPAN monitors all traffic, including multicast, and Bridge Protocol Data
Unit (BPDU) frames.
An ERSPAN source session is defined by the following parameters:
• A session ID
• List of source ports or source VLANs to be monitored by the session
• The destination and origin IP addresses, which are used as the destination and source IP addresses
of the GRE envelope for the captured traffic, respectively
• ERSPAN flow ID
• Optional attributes, such as, IP type of service (TOS) and IP Time to Live (TTL), related to the GRE
envelope
Note ERSPAN source sessions do not copy ERSPAN GRE-encapsulated traffic from source ports.
Each ERSPAN source session can have either ports or VLANs as sources, but not both.
An ERSPAN destination session is defined by the following parameters:
• Session ID
• Destination ports
• Source IP address, which is the same as the destination IP address of the corresponding source
session
• ERSPAN flow ID, which is used to match the destination session with the source session
• The ERSPAN source sessions copy traffic from the source ports or source VLANs and forwards the
traffic using routable GRE-encapsulated packets to the ERSPAN destination session. The ERSPAN
destination session switches the traffic to the destination ports
Note Because encapsulation is performed in the hardware, the CPU performance is not impacted.

Cisco Catalyst 4500 Series Specifications

General

Series	Catalyst 4500 Series
Category	Switch
Layer Support	Layer 2, Layer 3
Form Factor	Modular chassis
Stackable	No
Chassis Slots	3, 6, 7, 10
Power Supply Options	AC, DC
Redundancy	Power supply, Supervisor engine
Network Management	Cisco IOS Software CLI, SNMP, Cisco Prime Infrastructure
Features	Security, QoS
Port Density	Up to 384 ports per chassis
Security Features	802.1X, ACLs, DHCP Snooping, Dynamic ARP Inspection, IP Source Guard
Supervisor Engine	8-E