Wired Intelligent Edge

 View Only

  • 1.  Border Leader Leafs (Spine&Leafs) – how to transport more than 4096 VNIs between two sites?

    Posted Feb 02, 2026 04:23 AM

    Hi everyone,

    We have two Spine & Leaf fabrics located in two different sites. The sites are connected via Border Leader Leafs (two VSX stacks with four links). The setup itself is working fine, but due to the way VNIs, VLANs, and EVPN are implemented on Aruba switches, I cannot configure VNIs on the Border Leader Leafs without also configuring VLANs.
    For example:

    vlan 31
        vsx-sync
        name TEST
    evpn
        dyn-vxlan-tunnel-bridging-mode ibgp-ebgp
        vlan 31
            rd 10.100.x.2:10031
            route-target export 65101:10031
            route-target import 65101:10031
    interface vxlan 1
        source ip 10.100.x.2
        no shutdown
        vni 10030
            vlan 31

    So on the Border Leader Leafs I cannot configure more than 4096 VNIs, because I cannot have more than 4096 VLANs on a single switch.

    Now we are onboarding some "large" customers. These customers can have up to 3000 of their own VLANs. They get dedicated leaf switches. Within a single site everything works fine: the customers use their own VNI pools (for example 20000–25000 and 30000–35000), and their VLANs exist only on their own leafs.

    The problem appears when such a "large" customer needs connectivity in both sites. In that case, I would need to configure more than 6000 VLANs on the Border Leader Leafs, which is not possible.

    When I designed the two-site setup, I followed this documentation:
    https://arubanetworking.hpe.com/techdocs/AOS-CX/10.16/HTML/vxlan/Content/Chp_EV-VX-MF/ex_intro.htm

    So the question is: how do you transport more than 6000 VNIs (VLANs) between two sites in an Aruba EVPN Multisite design?

    Any examples or references would be highly appreciated. I assume I'm not the first one running into this limitation



    -------------------------------------------


  • 2.  RE: Border Leader Leafs (Spine&Leafs) – how to transport more than 4096 VNIs between two sites?

    Posted Feb 03, 2026 06:02 AM

    You could just ensure to have routing between the VTEP's on both sides. You don't need to terminate all VLAN's in the border switch. 



    ------------------------------
    Arne Opdal
    ------------------------------



  • 3.  RE: Border Leader Leafs (Spine&Leafs) – how to transport more than 4096 VNIs between two sites?

    Posted Feb 04, 2026 02:10 AM

    Could you please clarify what you mean?
    Within each site (and fabric) we are running iBGP, and eBGP is used between the fabrics. Naturally, the regular leaf switches (VTEPs) in different fabrics have routes to each other's Lo0 and Lo1.

    -------------------------------------------

    Original Message


  • 4.  RE: Border Leader Leafs (Spine&Leafs) – how to transport more than 4096 VNIs between two sites?

    Posted Feb 04, 2026 02:21 AM

    Just like you don't have same VID for different customers on one regular leaf, if you don't have anything ingress or egress on the VLAN you don't need the VLAN and VNI on the border leaf. Just ensure the routing is correct.

    Think of it a bit like a spine - how does the VXLAN go from leaf to leaf when no vlan / vni is on the spine?  



    ------------------------------
    Arne Opdal
    ------------------------------

    Original Message


  • 5.  RE: Border Leader Leafs (Spine&Leafs) – how to transport more than 4096 VNIs between two sites?

    Posted Feb 04, 2026 03:04 AM

    Wait, I'm a bit confused.
    I also used to think that VNIs and VLANs do not need to be configured on the Border Leader Leafs. However, in the documentation
    https://arubanetworking.hpe.com/techdocs/AOS-CX/10.16/HTML/vxlan/Content/Chp_EV-VX-MF/ex_fab1-config.htm
    under "Step 8.6 – Route-target adjustment for L2VNI", it states:

    "To extend a VLAN between fabrics, the VLAN and VNI must be configured on the border VTEP even if the said VLAN has no local member ports on the VTEP to downstream servers or switches."

    Without configuring the VLAN and VNI on the border VTEP, VLAN connectivity between the sites does not work. I have tested this.

    Is it possible to interconnect the sites in some other way that is not described in this document?

    -------------------------------------------

    Original Message


  • 6.  RE: Border Leader Leafs (Spine&Leafs) – how to transport more than 4096 VNIs between two sites?

    Posted Feb 04, 2026 05:43 AM

    Well , your usecase does not match the example in the document. You just have to figure out how to best get your routing of the VNIs between the sites.



    ------------------------------
    Arne Opdal
    ------------------------------

    Original Message


  • 7.  RE: Border Leader Leafs (Spine&Leafs) – how to transport more than 4096 VNIs between two sites?

    Posted Feb 04, 2026 05:59 AM

    That is exactly what my question in the previous post was about.
    What other options or best practices exist for interconnecting two sites in order to work around this 4096 VNI limitation?

    -------------------------------------------

    Original Message


  • 8.  RE: Border Leader Leafs (Spine&Leafs) – how to transport more than 4096 VNIs between two sites?

    Posted Feb 04, 2026 07:17 AM

    Sometimes you just have to create the solution yourself if it doesn't exist yet, or call a friend if you don't know how to achieve what you want ;-)
    You probably have a support contract or a integrator which could help you. Quick answers in a forum will probably not lead you the correct way.

    I would start with some experiments using the simulator to figure out how the routing must be to get your borders behave a little more like spines.



    ------------------------------
    Arne Opdal
    ------------------------------

    Original Message


Related Content