pfSense PVLAN on LACP trunk from Cisco 3172T NX-OS



  • I am investigating if I can use PVLANs on networks backed by my pfSense Netgate hardware. I have a pair of Cisco 3172T NX-OS switches that can be configured with PVLANs. My existing PVLANs use a Cisco ASA, which is aware of PVLANs and can have a "Secondary" VLAN added to a virtual interface to do the translation from an Isolated or Community VLAN to the Primary VLAN ID. I haven to found that pfSense has this ability, but wanted to see if anyone else was aware of how this might work. The switch pair is connected to an HA pair of pfSense boxes via two virtual port-channels and all VLANs are trunked on this port-channel.

    Any thoughts?


  • LAYER 8 Netgate

    No. pfSense is not Private VLAN-aware.

    It can certainly be placed on a private VLAN port like any other router but it does not understand the concept of private VLANs as described here:

    https://en.wikipedia.org/wiki/Private_VLAN

    if pfSense receives the traffic tagged with a dot1q tag it will behave appropriately.

    Segregating Private VLANs is a job for your layer 2 gear.



  • Yep I understand the purpose and where PVLANs should exist. My problem is that I am trunking many VLANs to pfSense, which means I cannot place it on a promiscuous port, but only also send the primary VLAN ID across the trunk. I am looking into a Cisco feature that would translate PVLAN secondary IDs to the primary ID across the trunk, but I am not confident it is supported with my switch model.


  • LAYER 8 Netgate

    pfSense speaks 802.1q. If you need different VLANs to be recognized, the switch needs to dot1q tag them.

    In general, when you use Private VLANs, EVERY DEVICE that speaks tagged traffic needs to understand Private VLANs. Else you lose the effect of Private VLANs.

    It's pretty easy to do on one switch. Multiple switches/devices especially across multiple vendors, not so much.



  • The PVLANs are tagged, but as you said, the issue is multiple devices and trunking in play here. Using the HA pair, two switches and the 10Gbps trunk means I either need pfSense to understand PVLANs or the Cisco switch to do the work for it. I am opening a ticket with Cisco to see if this model can do what is needed. Thanks for the response.


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