Written by 7:10 pm Load balancing

Round Robin Load Balancing. Simple and efficient

In this article we will focus on Round Robin Load Balancing. Such techniques are important because the traffic on the internet is constantly increasing. There are more devices connected and the data that circuit is more too. In order to manage all of this load, you need a load balancing solution that distributes it among the servers to reduce the load. Round Robin is the perfect solution in this situation! Let’s explain a little bit more about it!

What is Round Robin Load Balancing?

Round Robin Load Balancing is a simple technique for spreading incoming traffic across multiple servers. It cyclically forwards client requests via a group of servers to effectively balance the server load. It is excellent in cases when the servers are very similar in their computational and storage capacities. 

Round Robin Load Balancing is most commonly used because of its simplicity. Its implementation is rather straightforward. It is a distributor that redirects the traffic from different users to the servers in order. Let’s see an example. Imagine you have 6 users (u1, u2, u3, u4, u5 and u6) who want to connect and you have 3 servers (s1, s2 and s3). U1 will connect to s1, u2 to s2, u3 to s3 and it will start all over again u4 to s1, u5 to s2 and u6 to s3. Can you guess to which will it connect the next user 7? Yes, it will connect to s1.

It takes into account just when somebody wants to connect. Nothing more. It will definitely serve as a load balance, based on this logic, but ignore all other parameters. So you will have reduced load on the network, but you can have different problems.

Maybe your servers are not equal. Imagine server 1 (s1) is a lot faster than the rest. With more RAM, better CPU, etc. It will still receive the same traffic as the rest which are weaker. It is not the most efficient scenario. For that reason, Round Robin Load Balancing works best with the same configuration of servers.

How does Round Robin Load balancing work?

Round Robin Load Balancing functions under a very easy-to-understand mechanism. As we mentioned earlier, this technique forwards requests cyclically between servers. They are sequenced depending on the order they arrive. This mechanism is especially helpful during high incoming traffic and keeps the load balanced. 

Here is an illustration of how Round Robin Load Balancing actually works. Let’s imagine a company that holds a group of four servers: A, B, C, and D, and many users send requests to connect with their website:  

  • Server A gets request 1
  • Server B gets request 2
  • Server C gets request 3
  • Server D gets request 4

The rotation starts all over again when the load balancer continues to send requests to servers. 

But what if one of the servers has the capacity to handle more requests compared to others? Then you can implement Weighted Round Robin (WRR)!

Weighted Round Robin (WRR)

Weighted Round Robin is a little bit more advanced configuration for balancing the load. Yet, it is a perfect opportunity if one of your servers has better characteristics than the rest. The administrator can assign weight to every server in the group based on chosen criteria. In a most popular scenario, the criterion is the server’s traffic‑handling capacity.

This variation of Round Robin takes into account the previous case, where one server is better than the rest. Imagine the s1 is twice more powerful than s2 and s3. We will assign it higher weight because it can handle a more significant load. Because we did this, it will get more traffic.

Following the example, u1 will connect to s1, then u2 will again connect to s1. This is the main difference. U3 will connect to s2, u4 to s3, then again u5 to s1 and u6 to s1. U7 will connect to s2.
There is another scenario where Weighted Round Robin can be useful. Maybe your servers are similar, but you have more important information in one, you want it to have less weight. So, it that case you assign higher values to the rest of the servers. This way they will handle more load and your essential server will have less work and less chance to crush.

Suggested article: What is Load Balancing?

Advantages and Disadvantages

Here are the main benefits and drawbacks of the Round Robin Load Balancing mechanism:

Advantages: It is an easy-to-understand and easy-to-apply technique. Additionally, it does not require much effort to set up, works on a clear mechanism, and has an uncomplicated framework.

Disadvantages: The simplicity of this mechanism is also its main drawback, and many experienced administrators prefer to utilize Weighted Round Robin or more complicated algorithms. 

Can I use Round Robin Load Balancing with ClouDNS?

You can use Round Robin Load Balancing in every one of our plans, including the free plan. You can try it out HERE.

With this load balancing method, you can use A records, AAAA records and ALIAS records  but you can’t use CNAME records with any other DNS record for the same host.

Hope we have been useful. For any additional questions, you can get in contact with our SALES TEAM or if you are already a client with our TECHNICAL SUPPORT one.

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Tags: , , , , , Last modified: August 18, 2022