What action should be taken to increase the number of active Service Engines utilized by a Virtual Service?

The analysis assumes the options relate to different scaling methods. To increase the number of active Service Engines (SEs) for a single Virtual Service (VS), you must enable active-active scale-out. This is achieved by enabling scaleoutecmp (Equal-Cost Multi-Path) in the Virtual Service's advanced properties. This setting allows the VS to be placed on multiple SEs within its SE Group simultaneously. The upstream router then uses ECMP to distribute traffic across all active SEs, thereby increasing the VS's capacity and resilience. This is the primary mechanism for horizontal scaling of a Virtual Service.

A. Increasing vCPUs or memory on an SE is incorrect as this is vertical scaling, which enhances the capacity of a single SE but does not increase the number of active SEs.

C. Adding more servers to the backend pool is incorrect because this scales out the application tier, not the load balancing tier (the Service Engines).

D. Creating a new SE Group is incorrect. While a VS needs an SE Group, simply creating a new one does not automatically scale out an existing VS across more active SEs.

1. VMware NSX Advanced Load Balancer Documentation, "Virtual Service Scaling," Section on "Native Scaleout (ECMP)". This section explicitly details the function and configuration of scaleoutecmp.

2. VMware NSX Advanced Load Balancer Documentation, "Architecture and Components," Section on "Service Engines". The documentation describes the different scaling models, including N+M (scale-out) and vertical scaling.