Add Clusters

Connecting your Kubernetes clusters to Devtron is the foundation for deploying, observing, and managing applications across your infrastructure. This page walks you through the different ways to add a cluster, whether you are connecting an existing cluster, using a kubeconfig file, or working with isolated and air-gapped setups. You will also learn how to configure connection types, set up TLS, enable application metrics, and assign categories for better organization.

Connect Your Existing Kubernetes Cluster

Who Can Perform This Action?

Users need to have super-admin permission to add a Kubernetes cluster to Devtron.

1. Go to Global Configurations → Clusters & Environments → Connect Cluster (button); a New Cluster modal window will appear.

Figure 1: Adding a Cluster

2. Select Connect Cluster.

Figure 2: Selecting 'Connect Cluster'

3. You can choose to add your Kubernetes cluster using either of the following methods:

Method	Description
Server URL & Bearer Token	Use Server URL and Bearer Token to add a cluster.
Kubeconfig	Use Kubeconfig file to add a cluster.

Figure 3: Choosing a Method

4. Click Save Cluster and your cluster will be connected to Devtron.

Add Cluster Using Server URL & Bearer Token

Note

Refer to Get Cluster Credentials to learn the process of getting the Server URL and bearer token.

1. To add a Kubernetes cluster on Devtron using Server URL and Bearer Token, provide the following information:

Field	Description
Name	Enter the name of your cluster.
Server URL	Enter the Server URL of your cluster (with https) Note: We recommend using a self-hosted URL instead of a cloud-hosted URL.
Bearer Token	Paste the bearer token of your cluster

Figure 4: Enter Cluster Credentials

2. Complete the remaining steps (optional):

• Choose Connection Type
• Use Secure TLS Connection
• Configure Prometheus
• Assign a Category

Tip

If you have a kubeconfig file ready, you may skip the above process and refer to Add Cluster Using Kubeconfig instead.

Add Cluster Using Kubeconfig

In case you prefer to add clusters using kubeconfig, follow these steps:

1. Copy and paste your kubeconfig file into the editor. Alternatively, you may browse and select the file as well.

Figure 5: Choosing Kubeconfig Option

2. Click the Get Cluster button. This action will display the cluster details alongside the kubeconfig.

Figure 6: Get Cluster List from Kubeconfig

3. If your kubeconfig file lists multiple clusters, they will be displayed in the window. Use the checkboxes to select the desired cluster(s) and click Save.

Figure 7: Clicking Save

4. Click the saved cluster, and complete the remaining steps (optional):

• Choose Connection Type
• Use Secure TLS Connection
• Configure Prometheus
• Assign a Category

Note

Ensure that the kubeconfig file has admin permissions. It is crucial for Devtron to have the necessary administrative privileges; otherwise, it may encounter failures or disruptions during deployments and other operations. Admin permission is essential to ensure the smooth functioning of Devtron and to prevent any potential issues that may arise due to insufficient privileges.

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Create Kubernetes Cluster

Prerequisites

Who Can Perform This Action?

Only a Super-Admin can add an OCI Registry in Devtron.

To create an EKS cluster, you need:

• OpenTofu (tofu-controller) chart installed in your Devtron instance.

  Refer to Getting Started with OpenTofu for more information.

• FluxCD controller (flux2) chart installed in your Devtron instance

• Secret containing AWS credentials

Install OpenTofu

Follow the steps mentioned below to install OpenTofu:

1. Navigate to Global Configurations → Container/OCI Registry.

2. Refer to the following table and enter the information in the appropriate fields:

   Field	Value
   Registry provider	Other
   Registry type	Public Registry
   Name	tofu
   Registry URL	ghcr.io
   List of repositories	flux-iac/charts/tofu-controller

   
   

   

   Figure 8: Container/OCI Registry

3. Click Save. The tofu-controller chart will be displayed in the Chart Store page.

4. Navigate to Chart Store and search for tofu-controller in the search box.

5. Select the chart and click Configure & Deploy. The following page will be displayed.

   

   Figure 9: Tofu Controller Chart

6. Enter the app name (e.g., tofu-controller) in the App Name field.

7. Select your project in the Project drop-down box.

8. Select the environment where you want to deploy the chart in the Deploy to Environment drop-down box.

Important Note

The environment/namespace where you install OpenTofu must be the same environment/namespace where the FluxCD controller will be installed (the next step) to create the cluster.

9. Choose either Helm or GitOps if configured as the deployment method.

10. Click Deploy Chart. OpenTofu will be installed in your Devtron instance.

Now that OpenTofu is installed, you can install the FluxCD controller in your Devtron instance.

Install FluxCD Controller

Follow the steps mentioned below to install OpenTofu:

1. Navigate to Chart Store and search for flux2 in the search box.

   

   Figure 10: "flux2" Chart

2. Select the chart and click Deploy.

3. Enter the app name (e.g., tofu2) in the App Name field.

4. Select your project in the Project drop-down box.

5. Select the environment where you want to deploy the chart in the Deploy to Environment drop-down box.

Important Note

The environment/namespace where you install the FluxCD controller must be the same environment/namespace where OpenTofu was installed to create the cluster.

6. Choose either Helm or GitOps if configured as the deployment method.

7. Click Deploy Chart. FluxCD controller will be installed in your Devtron instance.

Now that FluxCD controller is installed, the final prerequisite is to create a secret containing your AWS credentials.

Create a Secret

Who Can Perform This Action?

User needs to be an Admin of the Kubernetes resource or a Super-Admin to create a Secret.

Follow the steps mentioned below to create a secret containing your AWS credentials:

1. Navigate to Resource Browser.

2. Click the default_cluster.

3. Click Create Resource.

4. Copy the YAML snippet given below and paste it in the Create Kubernetes Resource page.

   apiVersion: v1
   data:
     AWS_ACCESS_KEY_ID: SDKDI382DKD0=
     AWS_SECRET_ACCESS_KEY: YVZsSIEOwcFRSMjlvM2xaUjSIE823J3PT0=
   kind: Secret
   metadata:
     name: tf-aws-creds
     namespace: your-namespace
   type: Opaque

Important Note

• It is recommended to keep the name attribute to tf-aws-creds. Changing this value might make the secret go unrecognized.

• The secret must be created in the same namespace where OpenTofu and FluxCD controller are installed.

• When creating a secret, kindly ensure that your AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY are encoded in base64. Go to Devtron Base64 Encoder to encode your AWS credentials.

5. Enter your AWS access key against the AWS_ACCESS_KEY_ID attribute and AWS secret key against the AWS_SECRET_ACCESS_KEY attribute. Refer to Create New Access Keys for more information.

6. Click Apply. The secret will be created.

Now that all the prerequisites are met, you can proceed to create a cluster from the Create Kubernetes Cluster page.

Steps

Who Can Perform This Action?

Only a Super-Admin can create a Kubernetes cluster.

• Navigate to Global Configurations → Clusters & Environments → New Cluster → Create Kubernetes Cluster.

• Refer the following table (containing mandatory fields) and enter the details in the corresponding fields:

  Field	Description
  Cluster Provider	Select the type of cluster you'd like to create based on your requirement
  Name	Enter the name of your Kubernetes cluster (e.g., eks-cluster-nonprod in the case of EKS and rancher-cluster-qa in the case of Rancher)
  Region	Select the region where your cluster is hosted (e.g., us-east-1 in the case of EKS and ap-south-3 in the case of Rancher) Refer to View cluster details using the AWS Management Console for more information
  VPC CIDR	Enter the VPC CIDR value. This value determines the number of pods, nodes, or services your cluster can host (e.g., 10.0.1.6/16)
  Authentication Mode	Select the authentication mode you wish to perform for the cluster API_AND_CONFIG_MAP - Select this if you want to use both the API and the ConfigMap to authenticate who can access the cluster. This option is recommended if you are migrating from the old aws-auth ConfigMap method (which is deprecated) to the new API method. Refer to Grant IAM users access to Kubernetes with EKS access entries for more information. API - Select this if you want to manage access using a single API. This option is recommended as this is the best practice for EKS cluster creation. Refer to Manage User Access with API for more information. CONFIG MAP - Select this if you want to rely on the original (but deprecated) way of authentication using aws-auth ConfigMap. This option is not recommended anymore. Refer to Grant IAM users access to Kubernetes. with a ConfigMap. for more information.
  Enable IRSA	Turn on this IRSA toggle (IAM Roles for Service Accounts) if you want your application to securely connect to other AWS services using a service account
  Allow public access	Turn on this toggle if you want to allow your EKS control plane endpoint to be accessed publicly from anywhere without the VPC. It is recommended to keep this toggle disabled
  Cluster Version	Select your preferred Kubernetes cluster version. If you are running a live application in a production environment, it is recommended that you select a stable version instead of the latest version

  
  

  

  Figure 11: Create Kubernetes Cluster
  
  

• Refer the following table (containing optional fields) and enter the details in the corresponding fields:

  Field	Description
  Team	Select the team whose tag you want to attach to the cluster resources. For example, when you select qa-team, it means that the cluster resources (pods, ConfigMaps, etc.) created with this cluster are owned by the QA team
  Environment	Select the environment. For example, when you select qa, it means that this cluster is a part of the QA environment
  Availability Zones	Select availability zones (e.g., us-east-2b and ap-west-1a) if you prefer to distribute your worker nodes across multiple zones to make your cluster highly available. This means that even if one availability zone goes down (e.g., us-east-2b), the other zones (e.g., ap-west-1a) keep your cluster up and running
  Private access CIDRs	Enter the private access CIDRs (IP addresses that are allowed to reach the API server). If you had turned off the Allow public access toggle, then your EKS control plane endpoint would be private. It then becomes crucial to enter the private access CIDRs so that the API server recognizes them and allows them to access the endpoint

• Click Create Cluster.

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Add Isolated Cluster

Who Can Perform This Action?

Users need to have super-admin permission to add an isolated/air-gapped cluster to Devtron.

For air-gapped Kubernetes clusters with restricted inbound and outbound traffic, Devtron enables seamless management using isolated clusters. While these are not actual clusters with API endpoints, they provide a convenient way to deploy applications in such environments.

1. On the New Cluster modal window, select Add Isolated Cluster.

Figure 12: Selecting Isolated Cluster

2. Add a cluster name (e.g. banking-airgapped-cluster) and click Save Cluster.

Figure 13: Saving Isolated Cluster

You have successfully configured an isolated cluster.

Figure 14: New Isolated Cluster

Note

When you deploy to an isolated environment, Devtron automatically packages application manifests and images into a Helm chart. You can then either:

• Download and install manually in a fully air-gapped setup.
• Push it to an OCI registry (provided pushing of helm package is enabled), allowing manifests to be pulled manually or automatically via Devtron on an air-gapped cluster (if pull access to the OCI registry is available).

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Extras

Assign Category to a Cluster

Devtron allows you to assign a category (for e.g. Prod, QA, Dev, or Stage) to your clusters. This enables category-based filtering in the UI, allowing you to determine whether an application is deployed to the Prod, QA, Dev, or Stage environment.

Before assigning a category, you must first add the category. To add a category, refer to the Adding a Category section to learn more.

To assign a category to a cluster, follow the steps below:

1. Select a category from the dropdown under Assign Category and click Update Cluster.

   

   Figure 15: Assigning Category

2. The selected category will be assigned to the cluster.

   

   Figure 16: Category Assigned

Choose Method of Connection

When adding a new cluster to Devtron, you must choose how Devtron will connect to it. There are three connection options available:

Direct Connection

Clusters with a directly accessible API server endpoint, either publicly or via private peering, can be added as Direct Connection clusters.

• Devtron connects directly without an intermediary.
• Recommended when the cluster is publicly accessible or has a direct network route from Devtron.

Figure 17: Choosing Direct Connection

Via Proxy

For security reasons, some Kubernetes clusters are deployed behind a proxy. In this setup, Devtron routes all communication through the specified proxy URL.

• Use this option when network restrictions require traffic to go through a proxy server.
• Requires specifying a Proxy URL (e.g., http://proxy.example.org:3128).
• Limitation: Deployments via GitOps (ArgoCD) are not recommended for clusters connected via proxy.

Figure 18: Choosing 'Via Proxy'

Via SSH Tunnel

When a direct connection isn't possible, Devtron can connect to the Kubernetes cluster through an SSH tunnel, ensuring secure and encrypted communication.

• Requires:
  • SSH Server URL (e.g., http://proxy.example.org).
  • Username for authentication.
  • Authentication Method:
    • Password
    • SSH Private Key
    • Both Password & SSH Private Key
• Limitation: Deployments via GitOps (ArgoCD) are not recommended for clusters connected via SSH Tunnel.

Figure 19: Choosing 'Via SSH Tunnel'

Use Secure TLS Connection

For a secure cluster connection, you can opt for TLS connection, where you need to provide Certificate Authority Data, a TLS Key, and a TLS Certificate.

If your cluster is managed (e.g., EKS, AKS, GKE), you might need to download these certificates from your cloud provider’s dashboard or API.

Field	Description
Certificate Authority (CA) Data	The CA certificate (see: example) used to verify the Kubernetes API server’s identity.
TLS Key	The private key associated with the client certificate for authentication.
TLS Certificate	The client certificate used to authenticate with the Kubernetes API server.

Figure 20: Using Secure TLS Connection

Configure Prometheus (Enable Application Metrics)

If you want to see application metrics against the applications deployed in the cluster, Prometheus must be deployed in the cluster. Prometheus is a powerful tool to provide graphical insight into your application behavior.

Enable application metrics to configure Prometheus as shown below. In case it is not available, make sure to install the Monitoring (Grafana) integration from Devtron Stack Manager to configure Prometheus.

Figure 21: Enabling Application Metrics

Provide the information in the following fields:

Field	Description
Prometheus endpoint	Provide the URL of your Prometheus
Authentication Type	Prometheus supports two authentication types: Basic: If you select the Basic authentication type, then you must provide the Username and Password of Prometheus for authentication. Anonymous: If you select the Anonymous authentication type, then you do not need to provide the Username and Password. Note: The fields Username and Password will not be available by default.
TLS Key & TLS Certificate	These fields are optional and can be used when you use a customized URL.

Click Save Cluster to save your cluster on Devtron.

Get Cluster Credentials

Prerequisite

kubectl must be installed on the bastion.

Note

We recommend using a self-hosted URL instead of a cloud-hosted URL. Refer to the benefits of a self-hosted URL.

You can get the Server URL and Bearer Token by running the following command, depending on the cluster provider:

k8s Cluster Providers

If you are using EKS, AKS, GKE, Kops, Digital Ocean managed Kubernetes, run the following command to generate the server URL and bearer token:

curl -O https://raw.githubusercontent.com/devtron-labs/utilities/main/kubeconfig-exporter/kubernetes_export_sa.sh && bash kubernetes_export_sa.sh cd-user  devtroncd

Microk8s Cluster

If you are using a microk8s cluster, run the following command to generate the server URL and bearer token:

curl -O https://raw.githubusercontent.com/devtron-labs/utilities/main/kubeconfig-exporter/kubernetes_export_sa.sh && sed -i 's/kubectl/microk8s kubectl/g' \
kubernetes_export_sa.sh && bash kubernetes_export_sa.sh cd-user \
devtroncd

Figure 22: Generating Cluster Credentials

Benefits of Self-hosted URL

• Disaster Recovery:

  • You cannot edit the server URL of a cloud-specific provider. If you're using an EKS URL (e.g. *****.eu-west-1.elb.amazonaws.com), it will be a tedious task to add a new cluster and migrate all the services one by one.
  • But in case of using a self-hosted URL (e.g. clear.example.com), you can just point to the new cluster's server URL in DNS manager and update the new cluster token and sync all the deployments.

• Easy Cluster Migrations:

  • In case of managed Kubernetes clusters (like EKS, AKS, GKE etc) which is a cloud provider specific, migrating your cluster from one provider to another will result in waste of time and effort.
  • On the other hand, migration for a self-hosted URL is easy, as the URL belongs to a single hosted domain independent of the cloud provider.