Users Guide

618 Monitoring Switch Traffic
RSPAN cannot use the CPU as a mirror source. Instead, configure remote
capture to view packets sent to or from the switch CPU.
RSPAN Transit Switch
The following is an example of an RSPAN transit switch configuration. The
RSPAN VLAN should be configured as a remote-span in order to disable
MAC learning on the VLAN. In this case, the transit switch ports are
configured as trunk ports (members of all VLANs) and may be used by other
traffic. Packets on the transit switch (in this example) are received and
transmitted tagged.
1 Configure remote span on a VLAN:
console#configure
console(config)#vlan 723
console(config-vlan723)#remote-span
console(config-vlan723)#exit
2 Configure the transit switch ports in trunk mode:
console(config)#interface te1/0/1
console(config-if-Te1/0/1)#switchport mode trunk
console(config-if-Te1/0/1)#interface te1/0/2
console(config-if-Te1/0/2)#switchport mode trunk
RSPAN Destination Switch
The following example shows the configuration of the RSPAN destination
switch. The RSPAN mirrored packets are transmitted over the destination
port untagged. The destination port should be configured in access mode and
should not be a member of the RSPAN VLAN.
1 Configure remote span on VLAN 723:
console#configure
console(config)#vlan 723
console(config-vlan723)#remote-span
console(config-vlan723)#exit
2 Configure interface gi1/0/1 as the destination port. This port should not be
a member of the RSPAN VLAN.
console(config)#interface gi1/0/1
console(config-if-Gi1/0/1)#switchport mode access
console(config-if-Gi1/0/1)#exit