Cisco Systems 3750E manual 30-14

Chapter 30 Configuring SPAN and RSPAN

Configuring SPAN and RSPAN

This example shows how to remove any existing configuration on SPAN session 2, configure SPAN session 2 to monitor received traffic on all ports belonging to VLANs 1 through 3, and send it to destination Gigabit Ethernet port 2. The configuration is then modified to also monitor all traffic on all ports belonging to VLAN 10.

Switch(config)# no monitor session 2

Switch(config)# monitor session 2 source vlan 1 - 3 rx

Switch(config)# monitor session 2 destination interface gigabitethernet1/0/2

Switch(config)# monitor session 2 source vlan 10

Switch(config)# end

Creating a Local SPAN Session and Configuring Incoming Traffic

Beginning in privileged EXEC mode, follow these steps to create a SPAN session, to specify the source ports or VLANs and the destination ports, and to enable incoming traffic on the destination port for a network security device (such as a Cisco IDS Sensor Appliance).

For details about the keywords not related to incoming traffic, see the “Creating a Local SPAN Session” section on page 30-12.

	Command	Purpose
Step 1
	configure terminal	Enter global configuration mode.
Step 2
	no monitor session {session_number all	Remove any existing SPAN configuration for the session.
	local remote}
Step 3
	monitor session session_number source	Specify the SPAN session and the source port (monitored port).
	{interface interface-id vlan vlan-id} [, -]
	[both rx tx]
Step 4
	monitor session session_number	Specify the SPAN session, the destination port, the packet
	destination {interface interface-id[, -]	encapsulation, and the ingress VLAN and encapsulation.
	[encapsulation replicate] [ingress {dot1q	For session_number, specify the session number entered in Step 3.
	vlan vlan-id isl untagged vlan vlan-id
		For interface-id, specify the destination port. The destination
	vlan vlan-id}]}
		interface must be a physical port; it cannot be an EtherChannel, and
		it cannot be a VLAN.
		(Optional) [, -] Specify a series or range of interfaces. Enter a space
		before and after the comma or hyphen.
		(Optional) Enter encapsulation replicate to specify that the
		destination interface replicates the source interface encapsulation
		method. If not selected, the default is to send packets in native form
		(untagged).
		Enter ingress with keywords to enable forwarding of incoming
		traffic on the destination port and to specify the encapsulation type:
		• dot1q vlan vlan-id—Accept incoming packets with IEEE
		802.1Q encapsulation with the specified VLAN as the default
		VLAN.
		• isl—Forward ingress packets with ISL encapsulation.
		• untagged vlan vlan-idor vlan vlan-id—Accept incoming
		packets with untagged encapsulation type with the specified
		VLAN as the default VLAN.

	Catalyst 3750-E and 3560-E Switch Software Configuration Guide
30-14	OL-9775-02