Cisco Catalyst 3120 Command Reference Guide

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Cisco Catalyst Blade Switch 3120 for HP Command Reference
OL-12248-01
Chapter 2 Cisco Catalyst Blade Switch 3120 for HP Cisco IOS Commands
switchport mode private-vlan
We strongly recommend that you enable spanning tree Port Fast and bridge-protocol-data-unit (BPDU)
guard on isolated and community host ports to prevent STP loops due to misconfigurations and to speed
up STP convergence.
If you configure a port as a private-VLAN host port and you do not configure a valid private-VLAN
association by using the switchport private-vlan host-association interface configuration command,
the interface becomes inactive.
If you configure a port as a private-VLAN promiscuous port and you do not configure a valid private
VLAN mapping by using the switchport private-vlan mapping interface configuration command, the
interface becomes inactive.
Examples This example shows how to configure an interface as a private-VLAN host port and associate it to
primary VLAN 20. The interface is a member of secondary isolated VLAN 501 and primary VLAN 20.
Note When you configure a port as a private VLAN host port, you should also enable BPDU guard and Port
Fast by using the spanning-tree portfast bpduguard default global configuration command and the
spanning-tree portfast interface configuration command.
Switch# configure terminal
Switch(config)# interface gigabitethernet 1/0/1
Switch(config-if)# switchport mode private-vlan host
Switch(config-if)# switchport private-vlan host-association 20 501
Switch(config-if)# end
This example shows how to configure an interface as a private VLAN promiscuous port and map it to a
private VLAN. The interface is a member of primary VLAN 20 and secondary VLANs 501 to 503 are
mapped to it.
Switch# configure terminal
Switch(config)# interface gigabitethernet 1/0/2
Switch(config-if)# switchport mode private-vlan promiscuous
Switch(config-if)# switchport private-vlan mapping 20 501-503
Switch(config-if)# end
You can verify private VLAN switchport mode by using the show interfaces interface-id switchport
privileged EXEC command.
Related Commands Command Description
private-vlan Configures a VLAN as a community, isolated, or primary VLAN or
associates a primary VLAN with secondary VLANs.
show interfaces switchport Displays the administrative and operational status of a switching
(nonrouting) port, including private VLAN configuration.
switchport private-vlan Configures private VLAN associations and mappings between
primary and secondary VLANs on an interface.

Cisco Catalyst 3120 Specifications

General

Brand	Cisco
Model	Catalyst 3120
Category	Switch
Language	English