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Catalyst 2960 Switch SoftwareConfiguration Guide
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Chapter12 Configuring VLANs
Configuring VMPS
If the link goes down on a dynamic-access port, the port returns to an isolate d state and does not belong
to a VLAN. Any hosts that come online through the port are checked again through the VQP with the
VMPS before the port is assigned to a VLAN.
Dynamic-access ports can be used for direct host connections, or they can connect to a network. A
maximum of 20 MAC addresses are allowed per port on the switch. A dynamic-acc ess port can belong
to only one VLAN at a time, but the VLAN can change over time, depending on th e MAC addresses seen.
Default VMPS Client Configuration
Table12-6 shows the de fault VMPS and dynamic-access port configuration on client switches.
VMPS Configuration Guidelines
These guidelines and restrictions apply to dynamic-access port VLAN membership:
•You should configure the VMPS before you configure ports as dynamic-access ports.
•When you configure a port as a dynamic-access port, the spanning-tree Port Fast feature is
automatically enabled for that port. The Port Fast mode accelerates the process of bringing the port
into the forwarding state.
•IEEE 802.1x ports cannot be configured as dynamic-access ports. If you try to enable IEEE 802.1x
on a dynamic-access (VQP) port, an error message appears, and IEEE 802.1x is not enabled. If you
try to change an IEEE 802.1x-enabled port to dynamic VLAN assignment, an err or message appears,
and the VLAN configuration is not changed.
•Trunk ports cannot be dynamic-access ports, but you can enter the switchport access vlan dynamic
interface configuration command for a trunk port. In this case, the switch retains the setting and
applies it if the port is later configured as an access port.
You must turn off trunking on the port before the dynamic-access setting takes effect.
•Dynamic-access ports cannot be monitor ports.
•Secure ports cannot be dynamic-access ports. You must disable port security on a port before it
becomes dynamic.
•Dynamic-access ports cannot be members of an EtherChannel grou p.
•Port channels cannot be configured as dynamic-access ports.
•The VTP management domain of the VMPS client and the VMPS server must be the same.
•The VLAN configured on the VMPS server should not be a voice VLAN.
Table12-6 Default VMPS Client and Dynamic-Access Port Configuration
Feature Default Setting
VMPS domain server None
VMPS reconfirm interval 60 minutes
VMPS server retry count 3
Dynamic-access ports None configured