quickstart.md

Prerequisites:

In order to run the Postgres Operator locally in minikube you need to install the following tools:

• minikube
• kubectl

Note that you can also use built-in Kubernetes support in the Docker Desktop for Mac to follow the steps of this tutorial. You would have to replace minikube start and minikube delete with your launch actions for the Docker built-in Kubernetes support.

Clone the repository and change to the directory. Then start minikube.

git clone https://github.com/zalando/postgres-operator.git
cd postgres-operator

minikube start

Manual deployment setup

The Postgres Operator can be installed simply by applying yaml manifests.

kubectl create -f manifests/configmap.yaml  # configuration
kubectl create -f manifests/operator-service-account-rbac.yaml  # identity and permissions
kubectl create -f manifests/postgres-operator.yaml  # deployment

Helm chart

Alternatively, the operator can be installed by using the provided Helm chart which saves you the manual steps. Therefore, you would need to install the helm CLI on your machine. After initializing helm (and its server component Tiller) in your local cluster you can install the operator chart. You can define a release name that is prepended to the operator resource's names. Use --name zalando to match with the default service account name as older operator versions do not support custom names for service accounts.

# 1) initialize helm
helm init
# 2) install postgres-operator chart
helm install --name zalando ./charts/postgres-operator

Create a Postgres cluster

Starting the operator may take a few seconds. Check if the operator pod is running before applying a Postgres cluster manifest.

# if you've created the operator using yaml manifests
kubectl get pod -l name=postgres-operator

# if you've created the operator using helm chart
kubectl get pod -l app.kubernetes.io/name=postgres-operator

# create a Postgres cluster
kubectl create -f manifests/minimal-postgres-manifest.yaml

After the cluster manifest is submitted the operator will create Service and Endpoint resources and a StatefulSet which spins up new Pod(s) given the number of instances specified in the manifest. All resources are named like the cluster. The database pods can be identified by their number suffix, starting from -0. They run the Spilo container image by Zalando. As for the services and endpoints, there will be one for the master pod and another one for all the replicas (-repl suffix). Check if all components are coming up. Use the label application=spilo to filter and list the label spilo-role to see who is currently the master.

# check the deployed cluster
kubectl get postgresql

# check created database pods
kubectl get pods -l application=spilo -L spilo-role

# check created service resources
kubectl get svc -l application=spilo -L spilo-role

Connect to the Postgres cluster via psql

You can retrieve the host and port of the Postgres master from minikube. Retrieve the password from the Kubernetes Secret that is created in your cluster.

export HOST_PORT=$(minikube service acid-minimal-cluster --url | sed 's,.*/,,')
export PGHOST=$(echo $HOST_PORT | cut -d: -f 1)
export PGPORT=$(echo $HOST_PORT | cut -d: -f 2)
export PGPASSWORD=$(kubectl get secret postgres.acid-minimal-cluster.credentials -o 'jsonpath={.data.password}' | base64 -d)
psql -U postgres

Delete a Postgres cluster

To delete a Postgres cluster simply delete the postgresql custom resource.

kubectl delete postgresql acid-minimal-cluster

# tear down cleanly
minikube delete

Running and testing the operator

The best way to test the operator is to run it in minikube. Minikube is a tool to run Kubernetes cluster locally.

For convenience, we have automated starting the operator and submitting the acid-minimal-cluster. From inside the cloned repository execute the run_operator_locally shell script.

./run_operator_locally.sh

Note we provide the /manifests directory as an example only; you should consider adjusting the manifests to your particular setting.

Configuration Options

The operator can be configured with the provided ConfigMap (manifests/configmap.yaml) or the operator's own CRD. See developer docs for details.