Chapter 12
Configuring VLANs
Command
Step 11
interface gigabitethernet0/1
Step 12
spanning-tree vlan 2-4 cost 30
Step 13
end
Step 14
Step 15
exit
Step 16
show running-config
Step 17
copy running-config startup-config
Configuring VMPS
The VLAN Query Protocol (VQP) is used to support dynamic-access ports, which are not permanently
assigned to a VLAN, but given VLAN assignments based on the MAC source addresses seen on the port.
Each time an unknown MAC address is seen, the switch sends a VQP query to a remote VMPS; the query
includes the newly seen MAC address and the port on which it was seen. The VMPS responds with a
VLAN assignment for the port. The switch cannot be a VMPS server but can act as a client to the VMPS
and communicate with it through VQP.
This section includes this information about configuring VMPS:
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Understanding VMPS
Each time the client switch receives the MAC address of a new host, it sends a VQP query to the VMPS.
When the VMPS receives this query, it searches its database for a MAC-address-to-VLAN mapping. The
server response is based on this mapping and whether or not the server is in open or secure mode. In
secure mode, the server shuts down the port when an illegal host is detected. In open mode, the server
simply denies the host access to the port.
78-16156-01
"Understanding VMPS" section on page 12-27
"Default VMPS Client Configuration" section on page 12-29
"VMPS Configuration Guidelines" section on page 12-29
"Configuring the VMPS Client" section on page 12-29
"Monitoring the VMPS" section on page 12-32
"Troubleshooting Dynamic-Access Port VLAN Membership" section on page 12-33
"VMPS Configuration Example" section on page 12-33
Purpose
Enter interface configuration mode, and define the interface on which
to set the STP cost.
Set the spanning-tree path cost to 30 for VLANs 2 through 4.
Return to global configuration mode.
Repeat Steps 9 through 11 on the other configured trunk interface on
Switch A, and set the spanning-tree path cost to 30 for VLANs 8, 9, and
10.
Return to privileged EXEC mode.
Verify your entries. In the display, verify that the path costs are set
correctly for both trunk interfaces.
(Optional) Save your entries in the configuration file.
Catalyst 3560 Switch Software Configuration Guide
Configuring VMPS
12-27