The Couchbase Operator allows users to deploy Couchbase on OpenShift while significantly reducing the operational complexities typically association with managing and scaling databases.
Related resources:
- Autonomous Operator Overview
- Installing on OpenShift
- TODO: insert link to RHPDS setup steps.
This guide is intended to be run with with Red Hat's Partner Demo System for demos and workshops. It provides steps and examples for deploying Couchbase clusters using the Autonomous operator.
The first step is to login to Open Shift in your local browser AND terminal.
Open https://master.couchbase.openshiftworkshop.com/login in your browser and login with user1's credentials:
- username: user1
- password: openshift
Now we will login via terminal using opentlc-mgr's credentials:
oc login https://master.couchbase.openshiftworkshop.com
- username: opentlc-mgr
- password: r3dh4t1!
Note: opentlc-mgr is an admin account. Admin privileges are needed in order to install Custom Resource Definitions (CRDs).
Next, we need to create a project to work in.
oc new-project operator-example
This command creates the operator-example project and switches to it.
oc create -f crd.yaml
oc create -f cluster-role-sa.yaml
oc create -f cluster-role-user.yaml
oc create serviceaccount couchbase-operator --namespace operator-example
oc create rolebinding couchbase-operator --clusterrole couchbase-operator --serviceaccount operator-example:couchbase-operator
oc adm policy add-scc-to-user anyuid system:serviceaccount:operator-example:couchbase-operator
oc create rolebinding couchbasecluster --clusterrole couchbasecluster --user developer --namespace operator-example
oc create clusterrolebinding couchbasecluster --clusterrole couchbasecluster --user developer
Before we can deploy the operator we need to specify credentials for pulling container images from Red Hat's registry and add them to the service accounts.
Replace USERNAME and PASSWORD and EMAIL below with your Red Hat account info.
oc create secret docker-registry rh-catalog --docker-server=registry.connect.redhat.com --docker-username=redcouch --docker-password=openshift --docker-email=redcouchredhat@gmail.com
oc secrets add serviceaccount/couchbase-operator secrets/rh-catalog --for=pull
oc secrets add serviceaccount/default secrets/rh-catalog --for=pull
oc create -f operator.yaml
After < 1 minute you should be able to see the operator running:
oc get pods
NAME READY STATUS RESTARTS AGE
couchbase-operator-5bc785c54f-kh6c2 1/1 Running 0 22s
Do not proceed to the next step until you see the couchbase-operator pod has status RUNNING.
The Couchbase clusters deployed in the following steps will use the credentials provided in the cb-example-auth secret. Deplying secret.yaml will create the secret.
oc create -f secret.yaml
The first cluster that we'll deploy will be a simple, 4 node cluster, with one bucket and 2 replicas.
oc create -f cluster.yaml
You should start seeing Couchbase pods appearing immediately. It will take a couple of minutes for the cluster to be ready.
oc get pods
NAME READY STATUS RESTARTS AGE
cb-example-0000 1/1 Running 0 3m
cb-example-0001 1/1 Running 0 3m
cb-example-0002 1/1 Running 0 2m
cb-example-0003 1/1 Running 0 2m
couchbase-operator-5bc785c54f-kh6c2 1/1 Running 0 7m
Next, expose the Couchbase UI so you can log into it:
oc expose service/cb-example-ui
Get the route to the Couchbase UI:
oc get routes
NAME HOST/PORT PATH SERVICES PORT TERMINATION WILDCARD
cb-example-ui cb-example-ui-operator-example.apps.couchbase.openshiftworkshop.com cb-example-ui couchbase None
Open the URL outputted by oc get routes in your browser and login with "Administrator/password". Navigate to "Servers" to see the server list:
On the Pods page in OpenShift (https://master.couchbase.openshiftworkshop.com/console/project/operator-example/browse/pods):
Now that we have a cluster up and some data, we can demonstrate the operator in action.
First, delete one of the pods:
oc delete pod cb-example-0003
By deleting the pod, we are destroying one of the Couchbase nodes. At this point the operator should take over and try to recover the cluster to our desired state.
Couchbase recognizes that a node is missing and triggers fail-over:
Couchbase recognizes the new node coming online and begins rebalancing:
The rebalance conintues until the cluster is fully healed.
Delete the cluster before moving onto the next example:
oc delete -f cluster-basic.yaml
First, we need to add labels to our OpenShift nodes. Labels are used to tell the Operator which zone a particular node belongs to. In this example, we'll declare the node1 and node2 belong to ServerGroup1 and node2 and node3 belong to ServerGroup2.
oc label --overwrite nodes node1.couchbase.internal server-group.couchbase.com/zone=ServerGroup1
oc label --overwrite nodes node2.couchbase.internal server-group.couchbase.com/zone=ServerGroup1
oc label --overwrite nodes node3.couchbase.internal server-group.couchbase.com/zone=ServerGroup2
oc label --overwrite nodes node4.couchbase.internal server-group.couchbase.com/zone=ServerGroup2
Now deploy the new cluster:
oc create -f cluster-server-groups.yaml
This deploys a 9 node cluster with ServerGroups enabled. The distribution of nodes is setup so that each zone has 2 Data nodes and 1 Query node. This allows us to keep 2 replicas of the defauly bucket in each zone.
