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Catalyst 2950 and Catalyst 2955 Switch Software Configuration Guide
OL-10101-02
Chapter 24 Configuring SPAN and RSPAN
Configuring RSPAN
All participating switches support RSPAN.
Note The RSPAN VLAN cannot be VLAN 1 (the default VLAN) or VLAN IDs 1002 through
1005 (reserved to Token Ring and FDDI VLANs).
You should create an RSPAN VLAN before configuring an RSPAN source or destination session.
If you enable VTP and VTP pruning, RSPAN traffic is pruned in the trunks to prevent the unwanted
flooding of RSPAN traffic across the network for VLAN-IDs that are lower than 1005.
Configuring a VLAN as an RSPAN VLAN
First create a new VLAN to be the RSPAN VLAN for the RSPAN session. You must create the RSPAN
VLAN in all switches that will participate in RSPAN. If the RSPAN VLAN-ID is in the normal range
(lower than 1005) and VTP is enabled in the network, you can create the RSPAN VLAN in one switch,
and VTP propagates it to the other switches in the VTP domain. For extended-range VLANs (greater
than 1005), you must configure RSPAN VLAN on both source and destination switches and any
intermediate switches.
Use VTP pruning to get an efficient flow of RSPAN traffic, or manually delete the RSPAN VLAN from
all trunks that do not need to carry the RSPAN traffic.
Beginning in privileged EXEC mode, follow these steps to create an RSPAN VLAN:
To remove the remote SPAN characteristic from a VLAN and convert it back to a normal VLAN, use the
no remote-span VLAN configuration command.
This example shows how to create RSPAN VLAN 901.
Switch(config)# vlan 901
Switch(config-vlan)# remote span
Switch(config-vlan)# end
Command Purpose
Step 1 configure terminal Enter global configuration mode.
Step 2 vlan vlan-id Enter a VLAN ID to create a VLAN, or enter the VLAN ID of an
existing VLAN, and enter VLAN configuration mode. The range is
2 to 1001 and 1006 to 4094.
Note The RSPAN VLAN cannot be VLAN 1 (the default VLAN)
or VLAN IDs 1002 through 1005 (reserved for Token Ring
and FDDI VLANs).
Step 3 remote-span Configure the VLAN as an RSPAN VLAN.
Step 4 end Return to privileged EXEC mode.
Step 5 copy running-config startup-config (Optional) Save the configuration in the configuration file.