Home > Storage > ObjectScale and ECS > Product Documentation > Dell ECS with NGINX (OpenResty) > Highly available (redundancy)
In order to not have a single point of failure, it is best practice to setup NGINX in a “highly available” configuration by setting up two NGINX web servers. This provides redundancy such that in case of failure another load balancer is available to handle requests. A mechanism such as Linux’s “keepalived” utility can do health checks between the load balancers to inform NGINX when one of the web servers is not available. In a highly available setup, there are two ways to configure the redundant NGINX:
There are advantages and disadvantages of each method that should be considered. Since both load balancers are available for use in the active/active setup, the performance level is higher than in an active/passive setup. However, in an active/passive, there is a consistent performance level when one fails whereas in active/active when one fails, the performance level can drop by as much as half as perceived by clients. If certain “levels of service” are expected, then consistency is important to consider.
Upsizing the servers hosting the NGINX in an active/passive setup can improve performance; however, it may not be as cost-effective. Understanding the tradeoffs and requirements is important in developing a deployment best suited for your needs. Figure 3 provides an example of redundant NGINX web server in front of a pool of ECS Nodes with a virtual IP presented to clients.