High availability for DRE options

High availability for DRE can be set up using failover clustering or Hyper-V clustering for Server 2012 R2, 2016 and 2019 or Network Load Balancing (NLB).

Clustering uses multiple servers, as though they were a single system. In clustering, one resource runs, and another redundant resource is available to step in if the first one becomes unavailable. The purpose of HA clustering is to reduce the consequences of hardware, software, or network outages.

Network Load balancing uses multiple independent servers that have the same setup, but do not work together as in a cluster setup. The network load balancer (NLB) forward requests to either one server or another, but one server does not use the other server’s resources. Also, one resource does not share its state with other resources. In an NLB setup, all resources run at the same time, and a management layer distributes the workload across them.