29-22
Catalyst 3750 SwitchSoftware Configuration Guide
OL-8550-09
Chapter29 Configuring SPAN and RSPAN
Configuring SPAN and RSPAN
This example shows how to configure VLAN 901 as the source remote VLAN and port 1 as the
destination interface:
Switch(config)# monitor session 1 source remote vlan 901
Switch(config)# monitor session 1 destination interface gigabitethernet2/0/1
Switch(config)# end
Creating an RSPAN Destination Session and Configuring Incoming Traffic
Beginning in privileged EXEC mode, follow these steps to create an RSPAN destination session, to
specify the source RSPAN VLAN and the destination port, 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 an RSPAN Destination
Session” section on page 29-21. This procedure assumes that the RSPAN VLAN has already
been configured.
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 no monitor session
{session_number | all | local |
remote}
Remove any existing SPAN configuration for the session.
Step3 monitor session session_number
source remote vlan vlan-id
Specify the RSPAN session and the source RSPAN VLAN.
For session_number, the range is 1 to 66.
For vlan-id, specify the source RSPAN VLAN to monitor.
Step4 monitor session session_number
destination {interface interface-id
[, | -] [ingress {dot1q vlan vlan-id |
isl | untagged vlan vlan-id | vlan
vlan-id}]}
Specify the SPAN session, the destination port, the packet encapsulation, and
the incoming VLAN and encapsulation.
For session_number, enter the number defined in Step 4.
In an RSPAN destination session, you must use the same session number for
the source RSPAN VLAN and the destination port.
For interface-id, specify the destination interface. The destination interface
must be a physical interface.
Though visible in the command-line help string, encapsulation replicate is
not supported for RSPAN. The original VLAN ID is overwritten by the
RSPAN VLAN ID, and all packets appear on the destination port as untagged.
(Optional) [, | -] Specify a series or range of interfaces. Enter a space before
and after the comma; enter a space before and after the hyphen.
Enter ingress with additional keywords to enable forwarding of incoming
traffic on the destination port and to specify the encapsulation type:
dot1q vlan vlan-id—Forward incoming packets with IEEE 802.1Q
encapsulation with the specified VLAN as the default VLAN.
islForward ingress packets with ISL encapsulation.
untagged vlan vlan-id or vlan vlan-id—Forward incoming packets with
untagged encapsulation type with the specified VLAN as the default
VLAN.
Step5 end Return to privileged EXEC mode.