What is the benefit of Server Load Balancer (SLB)?

The purpose to deploy a server load balancer is to balance the traffic or requests from clients to servers.
A server load balancer (SLB) improves scalability, availability, manageability and performance of your web system.

1. Scalability - System admin can freely add or delete servers as needed.

2. Availability - SLB constantly checks the health status of each server and makes sure no traffic is directed to malfunctioning servers. Besides, you can often add a backup SLB to make sure the service will not stop even if the SLB itself crashes.

3. Manageability - System admin can know the server status through SLB and decides whether to add or reduce the number of servers. Besides, SLB decouples the applications from servers so that system admin can maintain servers without interrupting the service.

4. Performance - SLB makes sure that all servers operate at full capacity and no servers sit idle while others are overloaded. In other words, you will be able to utilize the maximum capacity of the whole system through SLB.