Private VLAN in Comware 7

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In Mai, I was on a proof of concept in Grenoble and one of the coolest things was the Private VLAN function in Comware 7. It was really interesting to see how it works and how simple it is to separate hosts from each other.
It works with a two-tier approach. There is a primary VLAN, which is used for L3 forwarding and interconnecting the secondary VLAN’s with each other when needed.
The secondary VLAN’s are used to put the clients in. Secondary VLAN’s are isolated on L2 from each other. It is configurable if clients in the same secondary VLAN’s can communicate with each other.

To test this feature, we used the 5900’s as access devices and core devices in the topology below:

We will create some secondary access VLAN’s on the IRF-Access devices.

VLAN 11
VLAN 12
VLAN 13
VLAN 14

The primary VLAN is VLAN 10, which needs also be configured:

vlan 10 
   private-vlan primary  
   private-vlan secondary 11 to 14

vlan 11 
   private-vlan isolated 

vlan 12 
   private-vlan isolated

vlan 13

vlan 14

The “private-vlan primary” statement will make VLAN 10 the primary VLAN. To make VLAN 11-14 a secondary VLAN in VLAN 10 use the second statement “private-vlan secondary VLANID”.

You do not have to make any special configurations for the secondary VLAN’s, except clients in the same secondary VLAN are not allowed to communicate with each other. Then you have to issue this statement in the VLAN contect of the secondary VLAN: “private-vlan isolated”

To configure the secondary VLAN’s on the access ports just issue those two commands on the access port:

port access vlan 11
port private-vlan host

Afterward, the port configuration should look like this:

#interface Ten-GigabitEthernet1/0/1 
   port link-mode bridge 
   port link-type hybrid 
   undo port hybrid vlan 1 
   port hybrid vlan 10 to 11 untagged 
   port hybrid pvid vlan 11 
   port private-vlan host  
   link-delay 0
#

Do this also for all the other ports. Next step is to configure the uplink port. Configure the port as a trunk port and permit the primary VLAN’s with this command.

port private-vlan 10 trunk promiscuous

The port configuration should look like this:

#interface Bridge-Aggregation10 
   description LINK TO DC1-CORE 
   port link-type trunk 
   undo port trunk permit vlan 1 
   port trunk permit vlan 10 to 14  
   port private-vlan 10 trunk promiscuous 
   link-aggregation mode dynamic
#

On the IRF-Core we just need to configure VLAN 10 as a normal VLAN with a VLAN interface and IP address, which will be the gateway for all clients in the secondary VLAN’s and offer L3 connectivity. Clients in VLAN 11 and 12 are not allowed to communicate with each other and with clients in VLAN 13 and 14. Clients in VLAN 13 and 14 are allowed to communicate with other clients within the same VLAN but not with Clients in other secondary VLAN’s. To allow inter VLAN communication between secondary VLAN’s you have to issue the following command on the VLAN 10 interface on IRF-Core:

local-proxy-arp enable

This will allow communication between secondary VLAN’s. As you can see, the configuration is very simple and handy.