High Availability Deployment Models

The High Availability feature supports the following deployment models:

• Standard HA—In this model, the Active and Standby Edges have the same configurations and have symmetric connections, that is both Edges are connected to the same WAN links. All ports on the Active Edge are open for receiving and sending traffic. Whereas all ports except GE1 on the Standby Edge are blocked. The GE1 interface is used to exchange heartbeats between Active and Standby Edges. See Standard HA.
• Enhanced HA – In this model, the Active and Standby Edges have the same configurations but have asymmetric connections, that is both Edges are connected to different WAN links. The GE1 interface is used to exchange heartbeats between Active and Standby Edges. The Active Edge can leverage the WAN link connected to the Standby Edge to send or receive traffic. It forwards the traffic through the GE1 interface to the Standby Edge, which in turn sends the traffic through the WAN link. See Enhanced HA.
• Mixed-mode HA—This model is a combination of both Standard and Enhanced HA deployments on the same site. In this model, the Active and Standby Edges have the same configurations. The connections can be both symmetric and asymmetric. See Mixed-Mode HA.

The HA options are supported on the following SD-WAN Edge platforms: 510, 510N, 520, 520v, 540, 610, 610N, 620, 620N, 640, 640N, 680, 680N, 840, 2000, 3400, 3800, 3810, and any Virtual Edge.

Note: HA Edges should be deployed within an isolated broadcast domain. During failover scenarios, to ensure a seamless transition of the Active role to the Standby Edge, it is crucial that the Standby Edge does not receive any incoming packets on the HA interface.

Caution: HA is supported only between identical SD-WAN Edge platform models. For more information on the Edge platform models, see https://sdwan.vmware.com/get-started.

Important: Prior to Edge Release 5.4.0, Edge models which did not include a Wi-Fi module (510N, 610N, 620N, 640N, and 680N) could not be used with a Wi-Fi capable counterpart in an HA deployment. For example, an Edge 640 and an Edge 640N were not supported as a High Availability pair. For Release 5.4.0 and forward, this pairing is now supported.

In a scenario with mismatched Wi-Fi and Non Wi-Fi Edges, the Orchestrator detects the Edge mismatch and automatically deactivates Wi-Fi capability on the Edge that is Wi-Fi capable. The mismatch log is shown in the customer's Events:

• "HA Wi-Fi capability mismatch identified, disabled Wi-Fi." (An Edge Wi-Fi mismatch is identified and Wi-Fi is deactivated on the Wi-Fi capable Edge).
• "HA Wi-Fi capability mismatch no longer seen, reverted Wi-Fi." (Both Edges are detected as the same Wi-Fi type, and Wi-Fi functionality is restored on a Wi-Fi Edge where it was previously deactivated).