About Private VLANs
The private VLAN (PVLAN) feature addresses two problems that service providers face when using VLANs:
       ·     The switch supports up to 1005 active VLANs. If a service provider assigns one VLAN per customer, this limits the numbers of customers the service provider can support.
       ·   To enable IP routing, each VLAN is assigned a subnet address space or a block of addresses, which can result in wasting the unused IP addresses, and cause IP address management problems

PVLAN Overview
Using PVLANs provides scalability and IP address management benefits for service providers and Layer 2 security for customers. PVLANs partition a regular VLAN domain into subdomains. A subdomain is represented by a pair of VLANs: a primary VLAN and a secondary VLAN. A PVLAN can have multiple VLAN pairs, one pair for each subdomain. All VLAN pairs in a PVLAN share the same primary VLAN. The secondary VLAN ID differentiates one subdomain from another
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Use Case
In our case VLAN 10 is Remote Management VLAN i.e. we have allowed VLAN10 over IPSEC tunnel .We have Jumpbox VM per Customer which has 2 NICs, 1 within Customer Network and 2 in Remote Management Network (VLAN 10). As VLAN 10 is common network between Customers using PVLANs we will be block communication between Customers over VLAN 10

Configuration Overview
Primary VLAN ID – 10
Secondary VLAN ID – 1010. It will be isolated

Virtual Machines
VM 1 :- (Promiscuous) :- DVPort Group as Promiscuous PG
VM2 :- (Isolated) :- DVPort Group as Isolated PG
VM3: (Isolated) :- DVPort Group as Isolated PG

Physical Switch Configuration
Primary VLAN Configuration
vlan 10
private-vlan primary 
private-vlan association 1010
Secondary VLAN Configuration
vlan 1010
private-vlan isolated
Switch Port Configuration. In our case it is gi0/2
Configure the port as trunk and allow primary and secondary vlans
switchport mode trunk
switchport trunk allowed vlan 10,1010
Layer 3 Configuration & Connectivity for Primary vlan
interface vlan 10
ip address
private-vlan mapping add 1010

DVSwitch Configuration
Create and configure PVLANs in dvswitch with VLAN 10 as primary and VLAN 1010 as isolated
Create Port Group for the dvswitch as Promiscuous VLAN along with VLAN ID as PVLAN
Create Port Group for ISOLATED VLAN along with VLAN ID as PVLAN
Map the VMs with the PortGroups
Edit the Settings for the all the 3 VMs and the Change the Network Label for the second NIC cards
Here we have changed the second NIC card to the Isolated PG for the Jumpbox VM
Assign IPs to the VMs and Test the functionality
Assign the IP Address as mentioned
VM 1 :- (Promiscuous) :- DVPort Group as Promiscuous PG
VM2 :- (Isolated) :- DVPort Group as Isolated PG
VM3: (Isolated) :- DVPort Group as Isolated PG

VM1 should be able to communicate to VM2 and VM3
VM2 should only communicate to VM1 not VM3
VM3 should only communicate to VM1 not VM2

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