StratosLive - A case study for WSO2 Load Balancer

In a cloud environment such as WSO2 StratosLive, auto-scaling becomes a crucial functionality. The system is expected to scale up and down with the dynamically changing load. Auto-scaling capabilities are sometimes provided by the Infrastructure as a Service provider themselves, such as the Autoscaling from Amazon. However, autoscaling is not necessarily a requirement that to be fulfilled by an IaaS. Say, you are providing Platform as a Service (PaaS) that is hosted over the pure native hardware, instead of an IaaS. In that case, your PaaS should be able to provide the required autoscaling and load balancing capabilities to the applications that are hosted on top of your platform. WSO2 Load Balancer is such a software load balancer, that handles the load balancing, fail over, and autoscaling functionalities.

WSO2 Load Balancer is used in production as a dynamic load balancer and autoscaler, as a complete software load balancer product. It is a stripped down version of WSO2 Enterprise Service Bus, containing only the components that are required for load balancing. WSO2 StratosLive can be considered a user scenario with WSO2 Load Balancer in production.

Multiple service groups are proxied by WSO2 Load Balancers. Some of the services have more than one instances to start with, to withstand the higher load. The system automatically scales according to the load that goes high and low. WSO2 Load Balancer is configured such that the permanent or the initial nodes are not terminated when the load goes high. The nodes that are spawned by the load balancer to handle the higher load will be terminated, when the load goes low. Hence, it becomes possible to have different services to run on a single instance, for the instances that are 'permanent', while the spawned instances will have a single carbon server instance.