Kubernetes Load Balancers: A Detailed Guide
The utility of Kubernetes in terms of accomplishing programming and other relevant tasks is undeniable. The journey of Kubernetes to become one of the leading orchestration platforms has been astounding so far. That’s what makes Kubernetes an exceptional choice to deal with your loads. For your information, the application or chain of applications you’re planning to run on Kubernetes are considered workloads. A Kubernetes user needs no separate introduction to the existence of pods in Kubernetes clusters. Generally, Kubernetes makes it possible to handle the loads you input with the help of the pods. Here comes the utility of Kubernetes load balancers.
However, you may not have developed familiarity with Kubernetes load balancers unless you’re a Kubernetes expert. You may be confused about what they are, why they are, and how to create them. If so, this article is for you to help you know everything about Kubernetes.
What are Load Balancers and Why are They Used?
In simple verse, load balancers are external software applications that help Kubernetes clusters to balance the load they are supposed to handle. Simultaneously, load balancers make it possible to distribute the loads among multiple pods based on their configurations to ensure uninterrupted workload.
Despite being an outstanding orchestration platform, Kubernetes is yet to consist of built-in load balancers or load-balancing architecture. That’s what insists users imply external load balancers to balance the workloads of Kubernetes clusters.
Coming to the reason, temporary lifespans of pods are the reasons why load balancers are essential for ensuring uninterrupted Kubernetes functions. Ideally, users get to create and destroy pods according to their requirements. Whenever you create a pod, a new IP address gets allocated for that pod. As a result, pods can’t be considered consistent ones to manage the loads on Kubernetes clusters. The IP addresses of pods lack stability and that becomes a barrier in terms of communication between pods.
Inter-communications between pods are significant to keep the functions of Kubernetes intact and uninterrupted. Therefore, an external load balancing software is implemented to distribute workloads among available pods in particular Kubernetes clusters.
In short, the absence of built-in load balancers makes it mandatory to utilize external load balancers to keep Kubernetes running.
Process of Creating an External Load Balancer to Manage Workloads in Kubernetes
Before diving into the main process, make sure you have created a Kubernetes cluster. Also, ensure that the kubectl command-line tool consists of the necessary configuration to initiate communication with the cluster. Also, it’s better if your Kubernetes cluster consists of two nodes.
The next step is all about creating the configuration file to move forward with the process. Don’t miss to add the line you find below to the service configuration file:
Conventionally, your configuration file is supposed to look identical with the following command:
– port: 8765
Apart from this, you can also opt for creating the service with the kubectl expose command. In this method, your service configuration file command is supposed to look something like this:
kubectl expose rc example –port=8765 –target-port=9376 \
With this command, you get the opportunity of creating a new service with the same selectors.
Efficient Kubernetes Load Balancing Strategies
1. Kube-proxy L4
This is the most convincing load balancing strategy in Kubernetes clusters. With Kube-proxy L4, you can field all incoming service requests of your Kubernetes cluster. At the same time, you get the chance to distribute them among the available pods to keep the workload unchanged.
2. Round Robin
With this load balancing strategy, you can create new connections and respond to new service requests with the eligible servers present in your Kubernetes cluster. However, this load balancing strategy is incapable of distributing the workload among servers according to their efficiencies. Therefore, a low-speed Kubernetes server is assumed to receive the same traffic that a high-speed Kubernetes server does.
3. Consistent hashing hash
Some external Kubernetes load balancers come with consistent hashing algorithms that allow these balancers to distribute workloads with distinct hashes. This load balancer is the best choice when it comes to balancing and distributing large loads among available servers and pods.
4. L7 Round Robin load balancing
Sometimes, you can’t take the risk of utilizing kube-proxy strategies in terms of distributing workloads among pods and servers. Well, the L7 Round Robin strategy allows users to route traffic to Kubernetes pods directly. Therefore, the process becomes clearer and straighter.
These are the popular load balancing strategies that are in practice in terms of load balancing and distributions. You’re supposed to select a preferred load balancing strategy to use an external load balancer efficiently.
Needless to mention, load balancers are integral parts of Kubernetes. Without them, most Kubernetes clusters tend to crash, which is miserable. You can’t afford to consider Kubernetes malfunctions while dealing with consistent, high workloads. In such scenarios, you should focus on balancing the incoming loads and that becomes effortless with external load balancers. So, we suggest you configure an external load balancer for your Kubernetes clusters to enjoy stable performances.