Top 5 Cluster Management Tools for Kubernetes in 2023

Kubernetes, also known as K8s, is a platform that allows you to efficiently manage your containerized applications across a group of machines. It simplifies the process of deploying, scaling, and updating your applications while ensuring reliability. Additionally, Kubernetes offers a range of features, including service discovery, load balancing, storage orchestration, and automatic self-recovery.

A Kubernetes cluster consists of a set of node machines for running your containers and pods – the fundamental building blocks in Kubernetes. The cluster also includes a control plane that maintains the desired state of the cluster. This involves managing which applications are currently running and their resource allocation. The control plane comprises components like the APl server, scheduler, controller manager, etc.

Challenges in Kubernetes Cluster Management

Despite its advantages, Kubernetes does present challenges. As organizations expand their usage of Kubernetes, As the clusters become larger in scale, managing them becomes increasingly complex and difficult. Users often encounter a range of challenges when working with Kubernetes, including:

• Cluster lifecycle and upgrade management: Keeping the cluster up and running and ensuring that it is updated with the latest patches and security fixes can be a daunting task. According to a survey by VMware, 41% of respondents reported difficulties in managing cluster lifecycles and upgrades, up 5% from last year.

• Integration with existing infrastructure: Integrating Kubernetes with the existing network, storage, security, and monitoring systems can be challenging, especially in hybrid and multi-cloud environments. The same survey found that 36% of respondents faced difficulties with integration into current infrastructure, up 6% from last year.

• Security and compliance: Ensuring that the cluster and the applications running on it are secure and compliant with the relevant regulations and policies can be a major concern. The survey revealed that 47% of respondents struggled with meeting security and compliance requirements, up 4% from last year.

• Resource utilization and optimization: Monitoring and managing the resource consumption and allocation of the cluster and the applications can be difficult, especially in large and dynamic clusters. The survey showed that 34% of respondents had difficulties with optimizing resource usage, up 3% from last year.

• Deployment and downtime mitigation: Deploying new applications or updates to existing ones can be risky, especially if there are errors or failures that affect the availability and performance of the cluster. The survey indicated that 31% of respondents had difficulties with deployment failovers and downtime mitigation, up 2% from last year.

• Visibility and troubleshooting: Having a clear and comprehensive view of the cluster and the applications, and being able to identify and resolve issues quickly and effectively, can be challenging, especially in multi-cluster and multi-cloud scenarios. The survey reported that 30% of respondents had difficulties with visibility and troubleshooting, up 1% from last year.

Overcoming the obstacles that arise during the adoption and implementation of Kubernetes, in organizations is crucial. To ensure an efficient management of Kubernetes clusters it is important to have access to the necessary tools and solutions. In this article we will talk about the top 5 Kubernetes cluster management tools in 2023 and discuss how they can assist in overcoming these challenges.

Criteria for selecting the best cluster management tools for Kubernetes

When it comes to choosing the cluster management tools for Kubernetes, there are various factors that you should take into account in order to ensure optimal cluster performance, security, and usability. Here are some key considerations when selecting the cluster management tools for Kubernetes:

• Ease of use: The tool should be straightforward to install, set up, and utilize. It’s important that it comes with a user interface and clear documentation. Additionally, the tool should have the capability to automate tasks and seamlessly integrate with tools and platforms. As an example, Kubectl serves as the command-line tool for Kubernetes, enabling users to interact with their cluster through commands.

• Features: The tool should have functionalities that cater to your requirements for managing clusters. These functionalities include creating, upgrading, backing up, monitoring, troubleshooting, scaling, and ensuring security. Additionally, the tool should be capable of supporting clusters and various cloud environments. It should also provide options for customization and extensibility. For instance, Rancher is a tool that offers a platform for managing Kubernetes clusters in settings. It enables you to incorporate custom plugins and applications.

• Integration: The tool needs to integrate with your current infrastructure, including network, storage, security, and monitoring systems. It should also be compatible with the version and distribution of Kubernetes you’re using, as well as support the cloud provider or platform you’re deploying on. For instance, Cert Manager is a tool that works alongside Kubernetes to handle certificate management for your cluster. It supports a range of certificate issuers, like Lets Encrypt, HashiCorp Vault, and AWS Certificate Manager.

• Scalability: The tool needs to be capable of managing the expansion and intricacy of your cluster while ensuring availability and reliability. It should also have the ability to optimize resource usage and allocation in your cluster, assisting you in cost reduction efforts. For example, Kops is a tool that helps you create, update, and delete production-grade Kubernetes clusters on AWS and supports cluster scaling, rolling updates, and cluster federation.

By evaluating these criteria, you can find the best cluster management tools for Kubernetes that suit your specific requirements and preferences.

Kubectl

Kubectl is a command-line utility that enables the execution of commands on Kubernetes clusters. Its features include deploying applications, overseeing cluster resources, and accessing logs. It stands out as the go-to tool for debugging and troubleshooting Kubernetes applications.

Architecture

Kubectl also uses a client-server architecture model. The Kubectl binary communicates with the Kubernetes API server that runs on the cluster’s control plane. Facilitating this interaction is a configuration file called kubeconfig, which houses details about the clusters, contexts, users, and namespaces. Kubectl can also use environment variables and flags to override the default settings.

The following diagram illustrates the kubectl architecture:

Pros and Cons

Some of the pros of using kubectl are:

• It is free and open source, with a large and active community.
• It is easy to install and use, and works with any Kubernetes version or distribution.
• It provides a comprehensive set of commands and flags to interact with various Kubernetes resources and features.
• It supports plugins and extensions that can enhance its functionality and usability.

Some of the cons of using kubectl are:

• It may not be suitable for complex or automated tasks, as it requires manual input and output processing.
• It may have some bugs or issues that affect the stability and performance of the tool, as it is still under active development.
• It may have some security risks, as it relies on the kubeconfig file and the API server, which may expose sensitive information or credentials.

How to Install and Use Kubectl

To install and use kubectl, you need to have a terminal program and a Kubernetes cluster that you can access. You can follow these steps to install and use kubectl:

1. Download the kubectl binary for your operating system from the Kubernetes release page. For example, to download the kubectl binary for Linux, you can run:

curl -LO "https://dl.k8s.io/release/v1.28.3/bin/linux/amd64/kubectl"

2. Make the kubectl binary executable and move it to a directory in your PATH. For example, to make the kubectl binary executable and move it to /usr/local/bin, you can run:

chmod +x ./kubectl
sudo mv ./kubectl /usr/local/bin/kubectl

3. Verify that kubectl is installed correctly by running:

kubectl version --client

4. Configure kubectl to connect to your cluster by creating or updating the kubeconfig file. You can use the kubectl config. command to manage the kubeconfig file, or use a tool provided by your cluster provider. For example, if you are using Google Kubernetes Engine, you can run:

gcloud container clusters get-credentials cluster-name

5. Test your connection to the cluster by running:

kubectl cluster-info

6. Use kubectl commands to interact with your cluster and its resources. You can use the kubectl cheat sheet to find the most common commands and flags. For example, to get the pods in the default namespace, you can run:

kubectl get pods

For more information, you can refer to the kubectl documentation.

Rancher

Rancher is a platform for managing containers that allows you to easily run and oversee Kubernetes clusters in different environments. With Rancher, you can work with Kubernetes distributions like RKE, [K3s, and RKE2, as well as leverage cloud-based Kubernetes services such as EKS, AKS, and GKE. Additionally, Rancher offers features like authentication, access control, monitoring capabilities, catalog management, and project management for your Kubernetes clusters.

Architecture

The Rancher system is made up of two parts: the Rancher server and the Kubernetes clusters that are connected to it. The Rancher server acts as a Kubernetes cluster, hosting the Rancher API server and additional components that enable the Rancher user interface and its features. The downstream Kubernetes clusters refer to the clusters that’re under the management of the Rancher server, which can be either created by Rancher itself or imported from sources.

The Rancher server interacts with the Kubernetes clusters by utilizing the Rancher agent. This agent is a pod that operates within each cluster. Its main function is to register the cluster with the Rancher server and establish a websocket connection for receiving commands and sending events. Additionally, the Rancher agent handles the deployment and management of Rancher components on the cluster, including the cluster agent, node agent, and drivers.

The following diagram illustrates the Rancher architecture:

Pros and Cons

Some of the pros of using Rancher are:

• It is free and open source, with a large and active community.
• It supports multiple Kubernetes distributions and cloud providers, giving you more flexibility and choice.
• It provides a user-friendly and intuitive UI, as well as a powerful CLI and API, for managing your Kubernetes clusters.
• It offers features that enhance the security, scalability, and usability of your Kubernetes clusters, such as RBAC, monitoring, backup, and catalog.

Some of the cons of using Rancher are:

• It adds another layer of complexity and overhead to your Kubernetes stack, which may increase the learning curve and maintenance cost.
• It may not support the latest versions or features of Kubernetes or the cloud providers, as it depends on the compatibility and integration of the Rancher components.
• It may have some bugs or issues that affect the stability and performance of your Kubernetes clusters, as it is still under active development.

How to Install and Use Rancher

To install Rancher, you need to have a Linux host with a supported Docker version and a Helm CLI. You can follow these steps to install Rancher on your host:

1. Add the Helm chart repository for Rancher:

helm repo add rancher-latest https://releases.rancher.com/server-charts/latest

2. Create a namespace for Rancher:

kubectl create namespace cattle-system

3. Choose your SSL configuration for Rancher. You can use either self-signed certificates, certificates from a recognized CA, or certificates from cert-manager. For example, to use self-signed certificates, you can run:

helm install rancher rancher-latest/rancher \
  --namespace cattle-system \
  --set hostname=rancher.my.org \
  --set tls=external

4. If you are using cert-manager, you need to install it before installing Rancher. You can run:

kubectl apply --validate=false -f https://github.com/jetstack/cert-manager/releases/download/v1.0.4/cert-manager.crds.yaml
kubectl create namespace cert-manager
helm repo add jetstack https://charts.jetstack.io
helm repo update
helm install cert-manager jetstack/cert-manager \
  --namespace cert-manager \
  --version v1.0.4

5. Install Rancher with Helm and your chosen certificate option. For example, to use cert-manager, you can run:

helm install rancher rancher-latest/rancher \
  --namespace cattle-system \
  --set hostname=rancher.my.org \
  --set ingress.tls.source=letsEncrypt \
  --set letsEncrypt.email=me@example.org

6. Verify that the Rancher server is successfully deployed by checking the pod status:

kubectl -n cattle-system rollout status deploy/rancher

To utilize Rancher, you can access the Rancher User Interface (UI) by opening a web browser and navigating to the hostname or address where the Rancher server has been installed. From there, you will be provided with step-by-step instructions on how to configure your cluster. You have two options: Create a new cluster using Rancher or import an existing one. You can also use the Rancher CLI or API to interact with your clusters and resources. For more information, you can refer to the Rancher documentation.

K9s

K9s is a terminal-based UI for seamless interaction with your Kubernetes clusters, enhancing the ease of navigating, observing, and managing deployed applications. The purpose of this tool is to make oversight of your deployed applications in different environments easier. By continually monitoring Kubernetes for changes, K9s offers relevant commands to interact with the observed resources.

Architecture

K9s uses a client-side architecture, running on your local machine, and communicates with your Kubernetes cluster through the kubectl command and the kubeconfig file. The benefits of K9s are that it does not need any installation or configuration on the cluster side, and it works seamlessly with various Kubernetes versions or distributions.

K9s provides a comprehensive dashboard that presents various information and metrics related to your cluster, including pods, nodes, services, deployments, and more. You can effortlessly switch between different views using keyboard shortcuts or commands. K9s also supports features such as filtering, searching, sorting, and grouping resources, as well as viewing logs, events, and shell access.

Pros and Cons

Some of the pros of using K9s are:

• It is free and open source, with a large and active community.
• It is easy to install and use and does not require any cluster-side setup or modification.
• It provides a user-friendly and intuitive UI, as well as a powerful CLI, for managing your Kubernetes clusters.
• It offers features that enhance the visibility, performance, and usability of your Kubernetes clusters, such as real-time metrics, error zoom, resource graph, and plugin support.

Some of the cons of using K9s are:

• It may not support some of the Kubernetes features or configurations that depend on the underlying infrastructure, such as load balancers, storage classes, or network policies.
• It may have some bugs or issues that affect the stability and performance of the tool, as it is still under active development.
• It may have some security risks, as it relies on the kubectl command and the kubeconfig file, which may expose sensitive information or credentials.

How to Install and Use K9s

To install and use K9s, you need to have a Linux, macOS, or Windows machine with a supported Kubectl version and a Kubeconfig file that allows you to access your Kubernetes cluster. You can follow these steps to install and use K9s:

1. Download the latest release of K9s from the GitHub page. You can choose the binary that matches your operating system and architecture. For example, to download the K9s binary for Linux 64-bit, you can run:

curl -Lo ./k9s https://github.com/derailed/k9s/releases/download/v0.28.2/k9s_Linux_x86_64.tar.gz

2. Extract the binary and move it to your PATH. For example, to extract and move the K9s binary for Linux 64-bit, you can run:

tar xvf k9s_Linux_x86_64.tar.gz
sudo mv k9s /usr/local/bin/k9s

3. Verify that K9s is installed correctly by running:

k9s version

4. Launch K9s by running:

k9s

5. You will see the K9s dashboard that shows the overview of your cluster and its resources. You can use the keyboard shortcuts or commands to switch between different views and perform actions on the resources. You can also use the ? key to see the help menu that lists the available commands and key bindings.

6. To exit K9s, you can use the :q or ctrl-c command.

Kops

Kops is a tool that enables you to easily create, manage, and remove Kubernetes clusters on AWS and other cloud platforms using the command line. It’s often compared to ‘kubectl’, for clusters, because it allows you to interact with your clusters through commands. Kops can also generate Terraform manifests for your clusters. Supports networking plugins and additional functionalities.

Architecture

Kops follows a declarative approach to cluster management, meaning that you define the desired state of your cluster using a YAML manifest, and then apply it using kops. Kops will then provision the necessary cloud resources, such as instances, load balancers, security groups, and DNS records, and install the Kubernetes components on them. Kops also creates a state store, which is a S3 bucket or a GCS bucket that stores the cluster configuration and secrets.

Pros and Cons

Some of the pros of using kops are:

• It is free and open source, with a large and active community.
• It supports multiple cloud platforms, giving you more flexibility and choice.
• It provides a user-friendly and intuitive CLI, as well as a powerful API, for managing your Kubernetes clusters.
• It offers features that enhance the security, scalability, and usability of your Kubernetes clusters, such as HA masters, rolling updates, and cluster federation.

Some of the cons of using kops are:

• It adds another layer of complexity and dependency to your Kubernetes stack, which may increase the learning curve and maintenance cost.
• It may not support the latest versions or features of Kubernetes or the cloud providers, as it depends on the compatibility and integration of the kops components.
• It may have some bugs or issues that affect the stability and performance of your Kubernetes clusters, as it is still under active development.

How to Install and Use Kops

To install kops, you need to have a Linux or macOS host with a supported kubectl version and a cloud provider account. You can follow these steps to install kops on your host:

1. Download the latest release of kops from the GitHub page:

curl -LO https://github.com/kubernetes/kops/releases/download/$(curl -s https://api.github.com/repos/kubernetes/kops/releases/latest | grep tag_name | cut -d '"' -f 4)/kops-linux-amd64

2. Make the binary executable and move it to your PATH:

chmod +x kops-linux-amd64
sudo mv kops-linux-amd64 /usr/local/bin/kops

3. Verify that kops is installed correctly:

kops version

To use kops you require a domain name for your cluster and a state store to store your cluster configuration and secrets. Follow these guidelines to use kops on AWS:

1. Create a hosted zone for your domain name using Route 53. For example, if your domain name is collabnix.com, you can create a hosted zone for k8s.collabnix.com:

ID=$(uuidgen) && aws route53 create-hosted-zone --name k8s.collabnix.com --caller-reference $ID | jq .DelegationSet.NameServers

2. Create a S3 bucket for your state store. For example, you can create a bucket named kops-state-store:

aws s3api create-bucket --bucket kops-state-store --region us-east-1

3. Enable versioning for your state store bucket:

aws s3api put-bucket-versioning --bucket kops-state-store --versioning-configuration Status=Enabled

4. Export the KOPS_STATE_STORE environment variable to point to your state store bucket:

export KOPS_STATE_STORE=s3://kops-state-store

5. Create a cluster configuration using the kops create cluster command. You can specify various options, such as the cluster name, the number and size of nodes, the networking plugin, and the cloud provider. For example, to create a cluster named mycluster.k8s.collabnix.com with 3 nodes of size t2.medium using Kubenet networking on AWS, you can run:

   kops create cluster --name=mycluster.k8s.collabnix.com --node-count=3 --node-size=t2.medium --networking=kubenet --cloud=aws

6. Review the cluster configuration using kops edit cluster command. You can modify the configuration as per your requirements. For example, to edit the cluster configuration for mycluster.k8s.collabnix.com, you can run:

kops edit cluster mycluster.k8s.collabnix.com

7. Apply the cluster configuration using the kops update cluster command. This will create the cloud resources and install the Kubernetes components for your cluster. You can also use the –yes flag to apply the changes immediately, or omit it to preview the changes. For example, to apply the cluster configuration for mycluster.k8s.collabnix.com, you can run:

kops update cluster mycluster.k8s.collabnix.com --yes

8. Verify that the cluster is ready using the kops validate cluster command. This will check the health and readiness of your cluster and nodes. For example, to validate the cluster for mycluster.k8s.collabnix.com, you can run:

kops validate cluster mycluster.k8s.collabnix.com

9. Access the cluster using the kubectl command. You can use the usual kubectl commands to interact with your cluster and resources. For example, to get the nodes in the cluster for mycluster.k8s.collabnix.com, you can run:

kubectl get nodes --show-labels

10. Delete the cluster using the kops delete cluster command. This will delete the cloud resources and uninstall the Kubernetes components for your cluster. You can also use the –yes flag to delete the cluster immediately or omit it to preview the changes. For example, to delete the cluster for mycluster.k8s.collabnix.com, you can run:

kops delete cluster mycluster.k8s.collabnix.com --yes

For more information, you can refer to the kops documentation.

Kind

The Kind tool can be used to set up a Kubernetes cluster by utilizing Docker containers as nodes. The term "kind" is short for "Kubernetes in Docker ". Its primary purpose is to facilitate the testing and development of Kubernetes applications on a machine. Additionally, Kind can be seamlessly integrated with Continuous Integration (CI) systems, allowing for the execution of Kubernetes tests in an isolated environment.

Architecture

To set up a cluster, Kind starts by launching one or more Docker containers. These containers run Kubernetes components, such as the API server, controller manager, scheduler, and Kubelet. Among these containers, one is designated as the control plane node, while the others function as worker nodes. To simulate the pod network in a Kubernetes cluster, these containers are interconnected through a Docker network. Additionally, Kind generates a file that grants you access to the cluster using tools like Kubectl or other Kubernetes utilities.

Pros and Cons

Some of the pros of using Kind are:

• It is free and open source, with a large and active community.
• It is easy to install and use, and does not require any special hardware or software dependencies.
• It is fast and lightweight, and can run multiple clusters on the same machine.
• It supports most of the Kubernetes features and configurations, and can run any Kubernetes version or distribution.

Some of the cons of using Kind are:

• It is not suitable for production use, as it does not provide high availability, scalability, or security guarantees.
• It may not support some of the Kubernetes features or configurations that depend on the underlying infrastructure, such as load balancers, storage classes, or network policies.
• It may have some bugs or issues that affect the stability and performance of the cluster, as it is still under active development.

How to Install and Use Kind

Kind supports all major operating systems – Linux, macOS, and Windows. Below you can find the installation steps for each OS.

Install Kind on Linux

1. Use the curl command to download Kind.

curl -Lo ./kind https://kind.sigs.k8s.io/dl/v0.20.0/kind-linux-amd64

2. Change the binary’s permissions to make it executable.

chmod +x ./kind

3. Move kind to an application directory, such as /usr/local/bin.

sudo mv ./kind /usr/local/bin/kind

Create a Cluster

Cluster management options in Kind are accessible through the kind command. Create a cluster by typing:

kind create cluster

The output shows the progress of the operation. When the cluster successfully initiates, the command prompt appears.

The command above bootstraps a Kubernetes cluster named kind. It uses a pre-built node image to create the control plane node and a worker node. To create a cluster with a different name, use the –name option.

kind create cluster --name=[cluster-name]

To create a cluster with a customized setup, including the desired number and type of nodes, the specific version of Kubernetes, or the preferred network settings, you can utilize the config option. Simply provide a YAML file that outlines your specifications. For instance, if you want to establish a cluster called "mycluster" with three worker nodes and Kubernetes version 1.21.1, refer to the following YAML file as an example:

# mycluster.yaml
kind: Cluster
apiVersion: kind.x-k8s.io/v1alpha4
nodes:
- role: control-plane
- role: worker
- role: worker
- role: worker
kubeadmConfigPatches:
- |
  kind: ClusterConfiguration
  metadata:
    name: config
  kubernetesVersion: v1.21.1

Then, run the command:

kind create cluster --name=mycluster --config=mycluster.yaml

Interact With Your Cluster

To interact with your cluster, you have the option to utilize Kubectl or any other Kubernetes tool. Kind automatically. It updates a file, which grants you access to the cluster. You can locate the kubeconfig file in the ~/.kube directory. Employ the kind get kubeconfig command to view its contents.

To work with your cluster using Kubectl, you have a couple of options. You can. Set the KUBECONFIG environment variable to indicate the location of the kubeconfig file. You can use the kubeconfig option along with kubectl. For instance, if you want to retrieve information about the nodes in your mycluster cluster, you can execute the command:

export KUBECONFIG="$(kind get kubeconfig-path --name=mycluster)"
kubectl get nodes

Or:

kubectl get nodes --kubeconfig="$(kind get kubeconfig-path --name=mycluster)"

You can also merge the kubeconfig file with your default kubeconfig file by using the command "export kubeconfig". Afterwards, you can conveniently use Kubectl with the context option. Let’s say you want to export the kubeconfig file for a cluster called "mycluster". In that case, just execute the command:

kind export kubeconfig --name=mycluster

Then, to get the pods in the cluster, you can run:

kubectl get pods --context=kind-mycluster

Delete a Cluster

To delete a cluster, use the kind delete cluster command and specify the cluster name. For example, to delete the cluster named mycluster, you can run:

kind delete cluster --name=mycluster

This will stop and remove the Docker containers that run the cluster nodes, and delete the kubeconfig file for the cluster.

Final Thoughts

In this article, we have explored different cluster management tools for Kubernetes in 2023. We’ve explored how these tools can assist in creating, operating, and scaling your Kubernetes clusters. Additionally, we’ve compared the advantages and disadvantages of each tool, along with instructions on their installation and usage.

However, it’s important to note that depending on factors such as cluster size, complexity, environment, and specific requirements, you may find some tools more suitable than others. Therefore, we recommend evaluating these tools based on the following criteria:

• Ease of use: How easy is it to install, configure, and use the tool? Does it provide a user-friendly interface and documentation? Does it support automation and integration with other tools and platforms?

• Features: What features does the tool offer to meet your cluster management needs? Does it support cluster creation, upgrade, backup, monitoring, troubleshooting, scaling, and security? Does it support multi-cluster and multi-cloud scenarios? Does it provide extensibility and customization options?

• Integration: How well does the tool integrate with your existing infrastructure, such as network, storage, security, and monitoring systems? Is it compatible with the Kubernetes version and distribution you are using? Does it support the cloud provider or platform you are deploying on?

• Scalability: How well does the tool handle the growth and complexity of your cluster? Does it provide high availability and reliability? Does it optimize the resource utilization and allocation of your cluster? Does it help you reduce costs?

By applying these guidelines, you can discover the optimal cluster management tools for Kubernetes that align with your requirements and preferences. We trust that this article has provided insights into the cluster management tools for Kubernetes and their efficient utilization.

Resources

• https://collabnix.github.io/kubetools/

• https://kubernetes.io/docs/tasks/tools/install-kubectl-linux/

• https://ranchermanager.docs.rancher.com/pages-for-subheaders/install-upgrade-on-a-kubernetes-cluster

• https://github.com/derailed/k9s

• https://phoenixnap.com/kb/kubernetes-kind

• https://github.com/kubernetes/kops/tree/master