Install OpenELB on Kubernetes

This document describes how to use kubectl and Helm to install and delete OpenELB in a Kubernetes cluster.

NOTE

  • In a Kubernetes cluster, you only need to install OpenELB once. After the installation is complete, a openelb-manager Deployment that contains a openelb-manager Pod is installed in the cluster. The openelb-manager Pod implements the functionality of OpenELB for the entire Kubernetes cluster.
  • After the installation is complete, you can scale the openelb-manager Deployment and assign multiple OpenELB replicas (openelb-manager Pods) to multiple cluster nodes to ensure high availability. For details, see Configure Multiple OpenELB Replicas.

Prerequisites

  • You need to prepare a Kubernetes cluster, and ensure that the Kubernetes version is 1.15 or later. OpenELB requires CustomResourceDefinition (CRD) v1, which is only supported by Kubernetes 1.15 or later. You can use the following methods to deploy a Kubernetes cluster:

    OpenELB is designed to be used in bare-metal Kubernetes environments. However, you can also use a cloud-based Kubernetes cluster for learning and testing.

    • If you use Helm to install OpenELB, ensure that the Helm version is Helm 3.

Install OpenELB Using kubectl

  1. Log in to the Kubernetes cluster over SSH and run the following command:

    kubectl apply -f https://raw.githubusercontent.com/openelb/openelb/master/deploy/openelb.yaml
    
  2. Run the following command to check whether the status of openelb-manager is READY: 1/1 and STATUS: Running. If yes, OpenELB has been installed successfully.

    kubectl get po -n openelb-system
    

    The following is an example of the expected command output:

    NAME                               READY   STATUS      RESTARTS   AGE
    openelb-admission-create-tjsqm     0/1     Completed   0          41s
    openelb-admission-patch-n247f      0/1     Completed   0          41s
    openelb-manager-74c5467674-bx2wg   1/1     Running     0          41s
    

Delete OpenELB Using kubectl

  1. To delete OpenELB, log in to the Kubernetes cluster and run the following command:

    kubectl delete -f https://raw.githubusercontent.com/openelb/openelb/master/deploy/openelb.yaml
    

    NOTE

    Before deleting OpenELB, you must first delete all Services that use OpenELB.
  2. Run the following command to check the result. If the openelb-system namespace does not exist, OpenELB has been deleted successfully.

    kubectl get ns
    

Install OpenELB Using Helm

  1. Log in to the Kubernetes cluster over SSH and run the following commands:

    helm repo add kubesphere-stable https://charts.kubesphere.io/stable
    helm repo update
    kubectl create ns openelb-system
    helm install openelb kubesphere-stable/openelb -n openelb-system
    
  2. Run the following command to check whether the status of openelb-manager is READY: 1/1 and STATUS: Running. If yes, OpenELB has been installed successfully.

    kubectl get po -n openelb-system
    

    The following is an example of the expected command output:

    NAMESPACE        NAME                              READY   STATUS      RESTARTS   AGE
    openelb-system   openelb-admission-create-m2p52    0/1     Completed   0          32s
    openelb-system   openelb-admission-patch-qmvnq     0/1     Completed   0          31s
    openelb-system   openelb-manager-74c5467674-pgtmh  1/1     Running     0          32s
    ... ...
    

Delete OpenELB Using Helm

  1. To delete OpenELB, run the following command:

    helm delete openelb -n openelb-system
    

    NOTE

    Before deleting OpenELB, you must first delete all Services that use OpenELB.
  2. Run the following command to check the result. If the OpenELB application does not exist, OpenELB has been deleted successfully.

    helm ls -n openelb-system
    

Last modified January 30, 2023: improve documentation (6d8b189)