There is no strict requirement that will prevent Controllers from managing remote SEs. However, it is essential to understand the best practices and ensure the deployment will scale with resilience.
It is recommended to deploy the Controller cluster and its Service Engines in the same data center. Tasks such as SE deployment (copying the SE image), log and metric collection, config propagation, and state backup (such as persistence tables) require connectivity. Increased latency can impact these operations and cause potential failures for data plane traffic.
If the latency is low enough, and the intent is to have the Controllers manage SEs in two or more data centers, redundant Controllers are recommended to be congregated in one data center. If the connectivity to the remote data center is lost, those SEs will not be able to receive configuration updates, but will continue to operate until connectivity is restored.
The RTT (round-trip time) value between an NSX Advanced Load Balancer Controller and SE must be less than 70 ms.
