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• Promiscuous port—A promiscuous port belongs to the primary VLAN. The promiscuous port can
communicate with all interfaces, including the community and isolated host ports, that belong to those
secondary VLANs associated to the promiscuous port and associated with the primary VLAN. You can
have several promiscuous ports in a primary VLAN. Each promiscuous port can have several secondary
VLANs or no secondary VLANs that are associated to that port. You can associate a secondary VLAN
to more than one promiscuous port, as long as the promiscuous port and secondary VLANs are within
the same primary VLAN. You may want to do this for load-balancing or redundancy purposes. You can
also have secondary VLANs that are not associated to any promiscuous port.
A promiscuous port can be configured as an access port.
• Isolated port—An isolated port is a host port that belongs to an isolated secondary VLAN. This port has
complete isolation from other ports within the same PVLAN domain, except that it can communicate
with associated promiscuous ports. PVLANs block all traffic to isolated ports except traffic from
promiscuous ports. Traffic received from an isolated port is forwarded only to promiscuous ports. You
can have more than one isolated port in a specified isolated VLAN. Each port is completely isolated
from all other ports in the isolated VLAN.
An isolated port can be configured an access port.
• Community port—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 associated
promiscuous ports. These interfaces are isolated from all other interfaces in other communities and from
all isolated ports within the PVLAN domain.
A community port must be configured as an access port.
Primary, Isolated, and Community Private VLANs
Primary VLANs and the two types of secondary VLANs (isolated and community) have these characteristics:
• Primary VLAN— The primary VLAN carries traffic from the promiscuous ports to the host ports, both
isolated and community, and to other promiscuous ports.
• Isolated VLAN —An isolated VLAN is a secondary VLAN that carries unidirectional traffic upstream
from the hosts toward the promiscuous ports. You can configure only one isolated VLAN in a PVLAN
domain. An isolated VLAN can have several isolated ports. The traffic from each isolated port also
remains completely separate.
• Community VLAN—A community VLAN is a secondary VLAN that carries upstream traffic from the
community ports to the promiscuous port and to other host ports in the same community. You can
configure multiple community VLANs in a PVLAN domain. The ports within one community can
communicate, but these ports cannot communicate with ports in any other community or isolated VLAN
in the private VLAN.
Cisco Nexus 3000 NX-OS Layer 2 Switching Configuration Guide, Release 5.0(3)U3(1)
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Configuring Private VLANs
Primary, Isolated, and Community Private VLANs