postgres-operator/docs/quickstart.md

131 lines
4.3 KiB
Markdown

## Prerequisites:
In order to run the Postgres Operator locally in minikube you need to install
the following tools:
* [minikube](https://github.com/kubernetes/minikube/releases)
* [kubectl](https://kubernetes.io/docs/tasks/tools/install-kubectl/#install-kubectl-binary-via-curl)
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.
```bash
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.
```bash
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
Another possibility is using a provided [Helm](https://helm.sh/) chart which
saves you these 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.
```bash
# 1) initialize helm
helm init
# 2) install postgres-operator chart
helm install --name postgres-operator ./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.
```bash
# 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](https://github.com/zalando/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.
```bash
# 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.
```bash
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.
```bash
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](https://kubernetes.io/docs/getting-started-guides/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.
```bash
./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](developer.md) for details.