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Private VLAN Configuration Example
The following example shows a private VLAN topology.
Figure 97. Sample Private VLAN Topology
The following configuration is based on the example diagram for the FN IOM switch:
● TenGig 0/0 and TenGig 0/23 are configured as promiscuous ports, assigned to the primary VLAN, VLAN 4000.
● TenGig 0/25 is configured as a PVLAN trunk port, also assigned to the primary VLAN 4000.
● TenGig 0/24 and TenGig 0/47 are configured as host ports and assigned to the isolated VLAN, VLAN 4003.
● TenGig 4/0 and TenGig 0/23 are configured as host ports and assigned to the community VLAN, VLAN 4001.
● TenGig 4/24 and TenGig 4/47 are configured as host ports and assigned to community VLAN 4002.
The result is that:
● The ports in community VLAN 4001 can communicate directly with each other and with promiscuous ports.
● The ports in community VLAN 4002 can communicate directly with each other and with promiscuous ports.
● The ports in isolated VLAN 4003 can only communicate with the promiscuous ports in the primary VLAN 4000.
● All the ports in the secondary VLANs (both community and isolated VLANs) can only communicate with ports in the other
secondary VLANs of that PVLAN over Layer 3, and only when the ip local-proxy-arp command is invoked in the
primary VLAN.
NOTE:
Even after you disable ip-local-proxy-arp (no ip-local-proxy-arp) in a secondary VLAN, Layer 3
communication may happen between some secondary VLAN hosts, until the ARP timeout happens on those secondary
VLAN hosts.
Inspecting the Private VLAN Configuration
The standard methods of inspecting configurations also apply in PVLANs.
To inspect your PVLAN configurations, use the following commands.
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Private VLANs (PVLAN)