Chapter 10 – Load Balancer Services for Linux
- If you are in a situation where your total load might be reaching the capacity of the load balancer, a DSR solution means that only the client to server traffic needs to be routed through the load balancer. This is especially impactful as most workloads have much more return traffic (server to client) than send traffic (from client to server). This means that changing to a DSR solution can easily reduce the traffic through the load balancer by 90%.
This performance is less of a consideration if smaller load balancers are matched 1:1 with each discrete workload that needs to be balanced. Especially in a virtualized environment, adding CPU and memory resources to a VM-based load balancer is also much simpler than the matching hardware upgrade might be in a legacy, hardware-based appliance situation.
A DSR load balancer also needs a fair bit of server and network "tinkering" to make all the pieces work. Once it works, figuring...