Comparison of Hybrid Web Cluster to a Next Gen Hardware Load Balancer / ADC (Application Delivery Controller)
Hardware Load Balancer
- Hardware load balancers, however reliable, are in themselves a single point of failure.
- Hardware load balancers generally have no knowledge of the actual load each server is under. They distribute requests across the servers so that each server receives the same number of requests, but each request may carry with it a greater cost in terms of processing (i.e. consider the difference between a request to resize a large JPEG vs. a request to serve a simple text file). The higher-end models do measure response time for a simple GET request, but this is a poor metric with respect to disk load and other factors which Hybrid Web Cluster takes into account.
Hybrid Cluster
- Hybrid Web Cluster has no single point of failure. In the event of a failure, other nodes will automatically take over from the failed node(s).
- Hybrid Web Cluster continually measures and communicates the amount of load each server is under. If one node is over-worked, it will hand over load to a different server, quickly, automatically, and without downtime.
