Cisco Catalyst 3560-X Software Configuration Manual page 516

Hide thumbs Also See for Catalyst 3560-X:

Table of Contents

Understanding Private VLANs

community VLAN

There are two types of secondary VLANs:

Isolated VLANs—Ports within an isolated VLAN cannot communicate with each other at the

Layer 2 level.

Community VLANs—Ports within a community VLAN can communicate with each other but

cannot communicate with ports in other communities at the Layer 2 level.

Private VLANs provide Layer 2 isolation between ports within the same private VLAN. Private-VLAN

ports are access ports that are one of these types:

Promiscuous—A promiscuous port belongs to the primary VLAN and can communicate with all

interfaces, including the community and isolated host ports that belong to the secondary VLANs

associated with the primary VLAN.

Isolated—An isolated port is a host port that belongs to an isolated secondary VLAN. It has

complete Layer 2 separation from other ports within the same private VLAN, except for the

promiscuous ports. Private VLANs block all traffic to isolated ports except traffic from promiscuous

ports. Traffic received from an isolated port is forwarded only to promiscuous ports.

Community—A community port is a host port that belongs to a community secondary VLAN.

Community ports communicate with other ports in the same community VLAN and with

promiscuous ports. These interfaces are isolated at Layer 2 from all other interfaces in other

communities and from isolated ports within their private VLAN.

Trunk ports carry traffic from regular VLANs and also from primary, isolated, and community VLANs.

Catalyst 3750-X and 3560-X Switch Software Configuration Guide

Private-VLAN Domain

isolated VLAN

Configuring Private VLANs

Troubleshooting

Catalyst 3750-x