32-17
Catalyst 3750-X and 3560-X Switch Software Configuration Guide
OL-21521-01
Chapter 32 Configuring SPAN and RSPAN Configuring SPAN and RSPAN
To monitor all VLANs on the trunk port, use the no monitor session session_number filter global
configuration command.
This example shows how to remove any existing configuration on SPAN session 2, configure SPAN
session 2 to monitor traffic received on Gigabit Ethernet trunk port 2, and send traffic for only VLANs 1
through 5 and VLAN 9 to destination Gigabit Ethernet port 1.
Switch(config)# no monitor session 2
Switch(config)# monitor session 2 source interface gigabitethernet1/0/2 rx
Switch(config)# monitor session 2 filter vlan 1 - 5 , 9
Switch(config)# monitor session 2 destination interface gigabitethernet1/0/1
Switch(config)# end
Configuring RSPAN
RSPAN Configuration Guidelines, page 32-17
Configuring a VLAN as an RSPAN VLAN, page 32-18
Creating an RSPAN Source Session, page 32-19
Specifying VLANs to Filter, page 32-20
Creating an RSPAN Destination Session, page 32-21
Creating an RSPAN Destination Session and Configuring Incoming Traffic, page 32-22

RSPAN Configuration Guidelines

All the items in the “SPAN Configuration Guidelines” section on page 32-12 apply to RSPAN.
As RSPAN VLANs have special properties, you should reserve a few VLANs across your network
for use as RSPAN VLANs; do not assign access ports to these VLANs.
You can apply an output ACL to RSPAN traffic to selectively filter or monitor specific packets.
Specify these ACLs on the RSPAN VLAN in the RSPAN source switches.
Step 5 monitor session session_number
destination {interface interface-id [, | -]
[encapsulation replicate]}
Specify the SPAN session and the destination port (monitoring port).
For session_number, specify the session number entered in Step 3.
For interface-id, specify the destination port. The destination 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; enter a space before and after the 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).
Step 6 end Return to privileged EXEC mode.
Step 7 show monitor [session session_number]
show running-config
Verify the configuration.
Step 8 copy running-config startup-config (Optional) Save the configuration in the configuration file.
Command Purpose