Load balancing uses a number of algorithms, called load balancing methods, to determine how to distribute the load among the servers. When a Load balancer is configured to use the least packets method, it selects the service with the least number transmitted and received packets.
Least Packets Load balancing allows you to distribute client requests across multiple servers to optimize resource utilization. Load balancers improve server fault tolerance and end-user response time. In a scenario with a limited number of servers providing service to a large number of clients, a server can become overloaded and degrade server performance. Load balancing is used to prevent bottlenecks by forwarding the client requests to the servers best suited to handle them. Thus, balancing the load.
In a load balancing setup, the load balancers are logically located between the client and the server farm. Load balancing is used to manage traffic flow to the servers in the server farm. The network diagram shows the topology of a basic load balancing configuration. Load Balancing can be performed on HTTP, HTTP, SSL, FTP, TCP, SSL_TCP, UDP, SSL_BRIDGE, NNTP, DNS, ANY, SIP-UDP, DNS-TCP, and RTSP.
The following example shows how a Load Balancer works using the least packets method. The load balancer selects the server by using the value (N) of the following expression:
N = Sum of the number of packets transmitted and received in last 14 seconds.
The load balancer delivers the requests as follows:
- Server-3 receives the first request because it has the lowest N value.
- Server-1 and Server-3 have the same N value, so round robin is performed.
- Server-1, Server-2 and Server-3 have the same N value, so round robin is performed until one of the N values changes.
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