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Private VLAN Configuration Example
The following example shows a private VLAN topology.
Figure 107. Sample Private VLAN Topology
The following configuration is based on the example diagram for the S5000–1:
● TenGig 0/0 and TenGig 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 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.
In parallel, on S5000-2:
● TenGig 0/3 is a promiscuous port and TenGig 0/25 is a PVLAN trunk port, assigned to the primary VLAN 4000.
● TenGig 0/4-6 are host ports. TenGig 0/4 and TenGig 0/5 are assigned to the community VLAN 4001, while TenGig 0/6 is
assigned to the isolated VLAN 4003.
The result is that:
● The S5000-2 ports would have the same intra-switch communication characteristics as described previously for the
S5000-1.
● For transmission between switches, tagged packets originating from host PVLAN ports in one secondary VLAN and destined
for host PVLAN ports in the other switch travel through the promiscuous ports in the local VLAN 4000 and then through the
trunk ports (0/25 in each switch).
Inspecting the Private VLAN Configuration
The standard methods of inspecting configurations also apply in PVLANs.
To inspect your PVLAN configurations, use the following commands.
672
Private VLANs (PVLAN)