Layer 2 VPN to the Cloud – Part II

Almost 3 years ago I have published an article how to set up layer 2 VPN between on-prem vSphere environment and vCloud Director Org VDC.

As both vCloud Director and NSX evolved quite a bit since to simplify the whole set up, here comes the part II.

Let me first summarize the use case:

The tenant has an application that resides on 3 different VLAN based networks running in its own (vSphere) datacenter. The networks are routed with existing physical router. The tenant wants to extend 2 of these networks to cloud for cloud bursting or DR purposes, but not the 3rd one (for example because there runs a physical database server).

The following diagram shows the setup.

The main advancements are:

  • vCloud Director natively supports NSX L2 VPN (VCD 8.20 or newer needed).
  • NSX now (since 6.2) supports configuration of unstretched networks directly (no static routes are necessary anymore)
  • This means the full setup can be done by the tenant in self-service fashion

Here are the steps:

  • The tenant will deploy freely available NSX Standalone Edge in its datacenter connected to trunk port with 2 VLANs mapped (10 and 11). Additional network configuration is necessary (forged transmits and promiscuous mode or sink port creation – see the link)
  • In the cloud Org VDC tenant deploys two routed Org VDC networks with identical subnets and gateways as networks A and B. These networks must be connected to the Org VDC Edge GW via subinterface (there can be up to 200 such networks on single Edge). The Org VDC Edge must have advanced networking enabled.
  • Tenant enables and configures L2VPN server on its Org VDC Edge GW. Note that this is a premium feature that the service provider must enable in Organization first (see this blog post).
  • Before the L2VPN tunnel is established the following must be taken into account:
    • The Org VDC Edge GW IP addresses are identical with the on-prem existing physical router. Therefore Egress Optimization Gateway addresses must be entered in the Peer Site configuration. That will prevent the Org VDC Edge GW from sending ARP replies over the tunnel.
    • The same must be performed on the Standalone NSX Edge via CLI (see egress-optimize command here).
    • The non-stretched network (subnet C) must be configured on the Org VDC Edge GW so it knows that the subnet is reachable through the tunnel and not via its upstream interface(s). This option however is not in vCloud UI, instead vCloud networking API must be used.
      Alternatively the provider could configure non-stretched network directly in the NSX UI:
    • Finally, the tunnel can be established by configuring L2VPN server details on the on-prem Standalone NSX Edge L2VPN client (endpoint IP, port, credentials, encryption) and providing VLAN to tunnel mappings.
    • Note to find the Org VDC network subinterface tunnel mapping vCloud API must be used again:

One thought on “Layer 2 VPN to the Cloud – Part II

  1. Hi Tom, we working on VCD (9) nsx (6.4) with l2vpn multi-tunnel, it can not pingable cross tunnel if egress-optimize enabled, opposite it work. May I know it is normal?
    We also tested unstretched netowrks, before your post we tested dedicated tunnel for osfp/bgp, and following your post test unstretched network seem not work. would share more experience on egress-optimize and unstretched networks, thanks.

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