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Load Balancer and Load balancing Algorithms


What is Load Balancer?

Load balancer is a virtual or physical device which distributes network traffic to clustered servers. It improves responsiveness and increases availability of applications.

Load balancer is an interface between client and server which acts as an advisor for the client network and request traffic. Passes the requests to the right server by using various load balancing algorithms.
Which reduces the load on single server and prevents any one application server from becoming a single point of failure. It results applications availability and response time.



Load balancer and Algos


Load Balancing Algorithms

There are lots of techniques and methods for load balancing algorithms. In a smart way handling the request and sending it to the right server. some might be complex algorithms. It is dependent what kind of system architecture you have.
Here are the few techniques.

Round Robin :Round robin passes the request to load balancer by one by one.

Example: if there are 3 load balancer they will get requests one by one. All they will be equally distributed to all servers.

Weighted Round Robin: It is similar as the round robin but servers get rating and as per the ratings servers get requests.
Smart load balancing calculates the load on the server and passes to the right server as per the load.

Least Connections: Servers with the least connection requests gets the next request.

Weighted Least Connections : Servers get rated with numerical value and when both servers have same number of connections rated one gets the priority.

Weighted Response Time: Load balancer calculates the health check response time to determine the fastest response time. At heavy load request are not sent to the particular server. Goes to the next server in the pool.


if you any questions or concerns regarding the blog let me know on aniketkarne@hotmail.com.


Happy Learning.. 😊

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