This blog post demonstrates how you can use the to deploy a Kubernetes Operator to your cluster. Then, you will use the Operator to spin up an Elastic Cloud on Kubernetes (ECK) cluster. Operator Lifecycle Manager An operator is a software extension that uses custom resources (extension of the Kubernetes API) to manage complex applications on behalf of users. The artifacts that come with an operator are: A set of that extend the behavior of the cluster without making any change in the code CRDs A controller that supervises the CRDs, and performs various activities such as spinning up a pod, take a backup, and so on. The complexity encapsulated within an Operator can vary, as shown in the below diagram: Image: Operator Maturity Model. Retrieved from https://docs.openshift.com/container-platform/4.1/applications/operators/olm-what-operators-are.html Prerequisites A Kubernetes cluster  (v1.7 or newer) with a control plane and two workers. If you don’t have a running Kubernetes cluster, refer to the “ ” section below. Create a Kubernetes Cluster with Kind Create a Kubernetes Cluster with Kind (Optional) Kind is a tool for running local Kubernetes clusters using Docker container "nodes". Follow the steps in  this section if you don't have a running Kubernetes cluster: Install kind by following the steps from the page. Kind Quick Start Place the following spec into a file named : kind-es-cluster.yaml kind: Cluster
apiVersion: kind.x-k8s.io/v1alpha4
nodes:
- role: control-plane
- role: worker
- role: worker 3. Create a cluster with a control plane and two worker nodes by running the Kind command followed by the flag and the name of the configuration file: create cluster --config kind create cluster --config kind-es-cluster.yaml Creating cluster ...
 ✓ Ensuring node image (kindest/node:v1.16.3) 🖼
 ✓ Preparing nodes 📦
 ✓ Writing configuration 📜
 ✓ Starting control-plane 🕹️
 ✓ Installing CNI 🔌
 ✓ Installing StorageClass 💾
 ✓ Joining worker nodes 🚜
Set kubectl context to You can now use your cluster with:

kubectl cluster-info --context kind-kind

Have a nice day! 👋 "kind" "kind-kind" 4. At this point, you can retrieve the list of services that were started on your cluster: kubectl cluster-info Kubernetes master is running at https://127.0.0.1:53519
KubeDNS is running at https://127.0.0.1:53519/api/v1/namespaces/kube-system/services/kube-dns:dns/proxy

To further debug and diagnose cluster problems, use . 'kubectl cluster-info dump' Install the Operator Lifecycle Manager In this section, you'll install the , a tool that helps you manage the Operators deployed to your cluster in an automated fashion. Operator Lifecycle Manager ("OLM") 1. Run the following commands to install OLM: curl -sL https://github.com/operator-framework/operator-lifecycle-manager/releases/download/0.13.0/install.sh | bash -s 0.13.0 customresourcedefinition.apiextensions.k8s.io/clusterserviceversions.operators.coreos.com created
customresourcedefinition.apiextensions.k8s.io/installplans.operators.coreos.com created
customresourcedefinition.apiextensions.k8s.io/subscriptions.operators.coreos.com created
customresourcedefinition.apiextensions.k8s.io/catalogsources.operators.coreos.com created
customresourcedefinition.apiextensions.k8s.io/operatorgroups.operators.coreos.com created
namespace/olm created
namespace/operators created
clusterrole.rbac.authorization.k8s.io/system:controller:operator-lifecycle-manager created
serviceaccount/olm-operator-serviceaccount created
clusterrolebinding.rbac.authorization.k8s.io/olm-operator-binding-olm created
deployment.apps/olm-operator created
deployment.apps/catalog-operator created
clusterrole.rbac.authorization.k8s.io/aggregate-olm-edit created
clusterrole.rbac.authorization.k8s.io/aggregate-olm-view created
operatorgroup.operators.coreos.com/global-operators created
operatorgroup.operators.coreos.com/olm-operators created
clusterserviceversion.operators.coreos.com/packageserver created
catalogsource.operators.coreos.com/operatorhubio-catalog created
Waiting deployment rollout to finish: 0 of 1 updated replicas are available...
deployment successfully rolled out
deployment successfully rolled out
Package server phase: Installing
Package server phase: Succeeded
deployment successfully rolled out for "olm-operator" "olm-operator" "catalog-operator" "packageserver" Install the ECK Operator The ECK Operator provides support for managing and monitoring multiple clusters, upgrading to new stack versions, scaling cluster capacity, etc. This section walks through installing the ECK Operator to your Kubernetes cluster: 1. Enter the following command to install the ECK Operator: kubectl apply kubectl apply -f https://download.elastic.co/downloads/eck/1.0.0/all-in-one.yaml customresourcedefinition.apiextensions.k8s.io/apmservers.apm.k8s.elastic.co created
customresourcedefinition.apiextensions.k8s.io/elasticsearches.elasticsearch.k8s.elastic.co created
customresourcedefinition.apiextensions.k8s.io/kibanas.kibana.k8s.elastic.co created
clusterrole.rbac.authorization.k8s.io/elastic-operator created
clusterrolebinding.rbac.authorization.k8s.io/elastic-operator created
namespace/elastic-system created
statefulset.apps/elastic-operator created
serviceaccount/elastic-operator created
validatingwebhookconfiguration.admissionregistration.k8s.io/elastic-webhook.k8s.elastic.co created
service/elastic-webhook-server created
secret/elastic-webhook-server-cert created 2. Remember that the ECK Operator is a Kubernetes resource. Thus, you can display it by using the following command: kubectl get CustomResourceDefinition NAME                                           CREATED AT
apmservers.apm.k8s.elastic.co                  2020-01-29T07:02:24Z
catalogsources.operators.coreos.com            2020-01-29T06:59:21Z
clusterserviceversions.operators.coreos.com    2020-01-29T06:59:20Z
elasticsearches.elasticsearch.k8s.elastic.co   2020-01-29T07:02:24Z
installplans.operators.coreos.com              2020-01-29T06:59:20Z
kibanas.kibana.k8s.elastic.co                  2020-01-29T07:02:25Z
operatorgroups.operators.coreos.com            2020-01-29T06:59:21Z
subscriptions.operators.coreos.com             2020-01-29T06:59:20Z 3. To see more details about a specific CRD, run the command followed by the name of the CRD: kubectl describe CustomResourceDefinition kubectl describe CustomResourceDefinition elasticsearches.elasticsearch.k8s.elastic.co Name:         elasticsearches.elasticsearch.k8s.elastic.co
Namespace:
Labels:       <none>
Annotations:  kubectl.kubernetes.io/last-applied-configuration:
                { : , : , :{ :{}, :null, "apiVersion" "apiextensions.k8s.io/v1beta1" "kind" "CustomResourceDefinition" "metadata" "annotations" "creationTimestamp" "name...
API Version:  apiextensions.k8s.io/v1
Kind:         CustomResourceDefinition
Metadata:
  Creation Timestamp:  2020-01-29T07:02:24Z
  Generation:          1
  Resource Version:    1074
  Self Link:           /apis/apiextensions.k8s.io/v1/customresourcedefinitions/elasticsearches.elasticsearch.k8s.elastic.co
  UID:                 2332769c-ead3-4208-b6bd-68b8cfcb3692
Spec:
  Conversion:
    Strategy:  None
  Group:       elasticsearch.k8s.elastic.co
  Names:
    Categories:
      elastic
    Kind:       Elasticsearch
    List Kind:  ElasticsearchList
    Plural:     elasticsearches
    Short Names:
      es
    Singular:               elasticsearch
  Preserve Unknown Fields:  true
  Scope:                    Namespaced
  Versions:
    Additional Printer Columns:
      Json Path:    .status.health
      Name:         health
      Type:         string
      Description:  Available nodes
      Json Path:    .status.availableNodes This output was truncated for brevity 4. You check the progress of the installation with: kubectl -n elastic-system logs -f statefulset.apps/elastic-operator { : , : , : , : , : , : , :1}
{ : , : , : , : , : , : , : }
{ : , : , : , : , : , : , : }
{ : , : , : , : , : , : , : }
{ : , : , : , : , : , : }
{ : , : , : , : , : , : , :1} "level" "info" "@timestamp" "2020-01-27T14:57:57.656Z" "logger" "controller-runtime.controller" "message" "Starting workers" "ver" "1.0.0-6881438d" "controller" "license-controller" "worker count" "level" "info" "@timestamp" "2020-01-27T14:57:57.757Z" "logger" "controller-runtime.controller" "message" "Starting EventSource" "ver" "1.0.0-6881438d" "controller" "elasticsearch-controller" "source" "kind source: /, Kind=" "level" "info" "@timestamp" "2020-01-27T14:57:57.758Z" "logger" "controller-runtime.controller" "message" "Starting EventSource" "ver" "1.0.0-6881438d" "controller" "elasticsearch-controller" "source" "kind source: /, Kind=" "level" "info" "@timestamp" "2020-01-27T14:57:57.759Z" "logger" "controller-runtime.controller" "message" "Starting EventSource" "ver" "1.0.0-6881438d" "controller" "elasticsearch-controller" "source" "channel source: 0xc00003a870" "level" "info" "@timestamp" "2020-01-27T14:57:57.759Z" "logger" "controller-runtime.controller" "message" "Starting Controller" "ver" "1.0.0-6881438d" "controller" "elasticsearch-controller" "level" "info" "@timestamp" "2020-01-27T14:57:57.760Z" "logger" "controller-runtime.controller" "message" "Starting workers" "ver" "1.0.0-6881438d" "controller" "elasticsearch-controller" "worker count" Note that the above output was truncated for brevity. 5. List the pods running in the namespace with: elastic-system kubectl get pods -n elastic-system NAME                 READY   STATUS    RESTARTS   AGE
elastic-operator-0   1/1     Running   0          11m Make sure the status is before moving on. Running Deploy an Elasticsearch Cluster In this section, we'll walk you through the process of deploying an Elasticsearch cluster with the Kubernetes Operator. 1. Create a file called with the following content: elastic-search-cluster.yaml apiVersion: elasticsearch.k8s.elastic.co/v1
kind: Elasticsearch
metadata:
  name: quickstart
spec:
  version: 7.5.2
  nodeSets:
  - name: default
    count: 2
    config:
      node.master: node.data: node.ingest: node.store.allow_mmap: true true true false Things to note in the above output: the parameter specifies the Elasticsearch version the Operator will deploy version the parameter sets the number of database nodes. Make sure it's not greater than the number of nodes in your Kubernetes cluster. count 2. Create a two-node Elasticsearch cluster by entering the following command: kubectl apply -f elastic-search-cluster.yaml elasticsearch.elasticsearch.k8s.elastic.co/quickstart created Behind the scenes, the Operator automatically creates and manages the resources needed to achieve the desired state. You can now run the following command to see the status of the newly created Elasticsearch cluster: kubectl get elasticsearch NAME         HEALTH    NODES   VERSION   PHASE   AGE
quickstart   unknown           7.5.2             3m51s Note that the status has not been reported yet. It takes a few minutes for the process to complete. Then, the status will show as : HEALTH HEALTH green kubectl get elasticsearch NAME         HEALTH   NODES   VERSION   PHASE   AGE
quickstart   green    2       7.5.2     Ready   8m47s 4. Check the status of the pods running in your cluster with: kubectl get pods --selector= 'elasticsearch.k8s.elastic.co/cluster-name=quickstart' NAME                      READY   STATUS    RESTARTS   AGE
quickstart-es- / Running m18s
quickstart-es- / Running m18s default -0 1 1 0 9 default -1 1 1 0 9 Verify Your Elasticsearch Installation To verify the installation, follow these steps. 1. The Operator exposes the service with a static IP address. Run the following command to see it: kubectl get service kubectl get service quickstart-es-http NAME                 TYPE        CLUSTER-IP      EXTERNAL-IP   PORT(S)    AGE
quickstart-es-http   ClusterIP   10.103.196.28   <none>        9200/TCP   15m 2. To forward all connections made to to port 9200 of the pod running the service, type the following command in a new terminal window: localhost:9200 quickstart-es-http kubectl port-forward service/quickstart-es-http 9200 Forwarding from 127.0.0.1:9200 -> 9200
Forwarding from [::1]:9200 -> 9200 3. Move back to the first terminal window. The password for the user is stored in a Kubernetes secret. Use the following command to retrieve the password, and save it into an environment variable called : elastic PASSWORD PASSWORD=$(kubectl get secret quickstart-es-elastic-user -o=jsonpath= | base64 --decode) '{.data.elastic}' 4. At this point, you can use to make a request: curl curl -u -k "elastic: " $PASSWORD "https://localhost:9200" { : , : , : , : { : , : , : , : , : , : , : , : , : }, : } "name" "quickstart-es-default-0" "cluster_name" "quickstart" "cluster_uuid" "g0_1Vk9iQoGwFWYdzUqfig" "version" "number" "7.5.2" "build_flavor" "default" "build_type" "docker" "build_hash" "8bec50e1e0ad29dad5653712cf3bb580cd1afcdf" "build_date" "2020-01-15T12:11:52.313576Z" "build_snapshot" false "lucene_version" "8.3.0" "minimum_wire_compatibility_version" "6.8.0" "minimum_index_compatibility_version" "6.0.0-beta1" "tagline" "You Know, for Search" Deploy Kibana This section walks through creating a new Kibana cluster using the Kubernetes Operator. 1. Create a file called with the following content: kibana.yaml apiVersion: kibana.k8s.elastic.co/v1
kind: Kibana
metadata:
  name: quickstart
spec:
  version: 7.5.1
  count: 1
  elasticsearchRef:
    name: quickstart
  podTemplate:
    metadata:
      labels:
        foo: kibana
    spec:
      containers:
        - name: kibana
          resources:
            requests:
              memory: 1Gi
              cpu: 0.5
            limits:
              memory: 1Gi
              cpu: 1 2. Enter the following command to create a Kibana cluster: kubectl apply kubectl apply -f kibana.yaml kibana.kibana.k8s.elastic.co/quickstart created 3. During the installation, you can check on the progress by running: kubectl get kibana NAME         HEALTH   NODES   VERSION   AGE
quickstart                    7.5.1     3s Note that in the above output, the status hasn't been reported yet. HEALTH Once the installation is completed, the status will show as green: HEALTH kubectl get kibana NAME         HEALTH   NODES   VERSION   AGE
quickstart   green    1       7.5.1     104s 4. At this point, you can list the Kibana pods by entering the following command: kubectl get pods kubectl get pod --selector= 'kibana.k8s.elastic.co/name=quickstart' NAME                             READY   STATUS    RESTARTS   AGE
quickstart-kb-7578b8d8fc-ftvbz   1/1     Running   0          70s Verify Your Kibana Installation Follow these steps to verify your Kibana installation. 1. The Kubernetes Operator has created a service for Kibana. You can retrieve it like this: ClusterIP kubectl get service quickstart-kb-http NAME                 TYPE        CLUSTER-IP     EXTERNAL-IP   PORT(S)    AGE
quickstart-kb-http   ClusterIP   10.98.126.75   <none>        5601/TCP   11m 2. To make the service available on your host, type the following command in a new terminal window: kubectl port-forward service/quickstart-kb-http 5601 Forwarding from 127.0.0.1:5601 -> 5601
Forwarding from [::1]:5601 -> 5601 3. To access Kibana, you need the password for the user. You've already saved it into an environment variable called in Step 3 of the section. You can now display it with: elastic PASSWORD Verify Your Elasticsearch Installation echo $PASSWORD vrfr6b6v4687hnldrc72kb4q In our example, the password is vrfr6b6v4687hnldrc72kb4q but yours will be different. 4. Now, you can access Kibana by pointing your browser to https://localhost:5601 5. Log in using the username and the password you retrieved earlier: elastic Manage Your ECK Cluster with the Kubernetes Operator In this section, you'll learn how to scale down and up your ECK Cluster. 1. To scale down, modify the number of nodes running Elasticsearch by specifying in your file. Your spec should look like this: nodeSets.count: 1 elasticsearch.yaml apiVersion: elasticsearch.k8s.elastic.co/v1
kind: Elasticsearch
metadata:
  name: quickstart
spec:
  version: 7.5.2
  nodeSets:
  - name: default
    count: 1
    config:
      node.master: node.data: node.ingest: node.store.allow_mmap: true true true false 2. You can apply the spec with: kubectl apply -f elastic-search.yaml elasticsearch.elasticsearch.k8s.elastic.co/quickstart configured Behind the scenes, the Operator makes required changes to reach the desired state. This can take a bit of time. 3. In the meantime, you can display the status of your cluster by entering the following command: kubectl get elasticsearch NAME         HEALTH   NODES   VERSION   PHASE             AGE
quickstart   green    1       7.5.2     ApplyingChanges   56m In the above output, note that there's only one node running Elasticsearch. 4. You can list the pods running Elasticsearch: kubectl get pods --selector= 'elasticsearch.k8s.elastic.co/cluster-name=quickstart' NAME                      READY   STATUS    RESTARTS   AGE
quickstart-es-default-0   1/1     Running   0          58m 5. Similarly, you can scale up your Elasticsearch cluster by specifying in your file: nodeSets.count: 2 elasticsearch.yaml apiVersion: elasticsearch.k8s.elastic.co/v1
kind: Elasticsearch
metadata:
  name: quickstart
spec:
  version: 7.5.2
  nodeSets:
  - name: default
    count: 3
    config:
      node.master: node.data: node.ingest: node.store.allow_mmap: true true true false 6. You can monitor the progress with: kubectl get elasticsearch NAME         HEALTH   NODES   VERSION   PHASE             AGE
quickstart   green    1       7.5.2     ApplyingChanges   61m Once the desired stats is reached, the column will show as : PHASE Ready kubectl get elasticsearch NAME         HEALTH   NODES   VERSION   PHASE   AGE
quickstart   green    2       7.5.2     Ready   68m Congratulations, you've covered a lot of ground, and now you are familiar with the basic principles behind the Kubernetes Operator! In a future post, we'll walk through the process of writing our own Operator. Thanks for reading! This article was originally published on https://appfleet.com/blog/first-steps-with-the-kubernetes-operator/ .

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