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● Community port — a port that belongs to a community VLAN and is allowed to communicate with other ports in the same
community VLAN and with promiscuous ports.
● Host port — in the context of a private VLAN, is a port in a secondary VLAN:
○ The port must first be assigned that role in INTERFACE mode.
○ A port assigned the host role cannot be added to a regular VLAN.
● Isolated port — a port that, in Layer 2, can only communicate with promiscuous ports that are in the same PVLAN.
● Promiscuous port — a port that is allowed to communicate with any other port type in the PVLAN:
○ A promiscuous port can be part of more than one primary VLAN.
○ A promiscuous port cannot be added to a regular VLAN.
● Trunk port — carries traffic between switches:
○
A trunk port in a PVLAN is always tagged.
○ In tagged mode, the trunk port carries the primary or secondary VLAN traffic. The tag on the packet helps identify the
VLAN to which the packet belongs.
○ A trunk port can also belong to a regular VLAN (non-private VLAN).
Each of the port types can be any type of physical Ethernet port, including port channels (LAGs).
Using the Private VLAN Commands
To use the PVLAN feature, use the following commands.
● Enable/disable Layer 3 communication between secondary VLANs.
INTERFACE VLAN mode
[no] ip local-proxy-arp
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 address resolution protocol (ARP) timeout
happens on those secondary VLAN hosts.
● Set the mode of the selected VLAN to community, isolated, or primary.
INTERFACE VLAN mode
[no] private-vlan mode {community | isolated | primary}
● Map secondary VLANs to the selected primary VLAN.
INTERFACE VLAN mode
[no] private-vlan mapping secondary-vlan vlan-list
● Display type and status of PVLAN interfaces.
EXEC mode or EXEC Privilege mode
show interfaces private-vlan [interface interface]
● Display PVLANs and/or interfaces that are part of a PVLAN.
EXEC mode or EXEC Privilege mode
show vlan private-vlan [community | interface | isolated | primary | primary_vlan |
interface interface]
● Display primary-secondary VLAN mapping.
EXEC mode or EXEC Privilege mode
show vlan private-vlan mapping
● Set the PVLAN mode of the selected port.
INTERFACE
switchport mode private-vlan {host | promiscuous | trunk}
NOTE:
Secondary VLANs are Layer 2 VLANs, so even if they are operationally down while primary VLANs are operationally
up, Layer 3 traffic is still transmitted across secondary VLANs.
NOTE: The outputs of the show arp and show vlan commands provide PVLAN data. For more information, refer to the
Dell EMC Networking OS Command Line Reference Guide.
716 Private VLANs (PVLAN)