Quickstart
Can’t wait to try out the PGO, the Postgres Operator from Crunchy Data? Let us show you the quickest possible path to getting up and running.
Prerequisites
Please be sure you have the following utilities installed on your host machine:
kubectl
git
Installation
Step 1: Download the Examples
First, go to GitHub and fork the Postgres Operator examples repository:
https://github.com/CrunchyData/postgres-operator-examples/fork
Once you have forked this repo, you can download it to your working environment with a command similar to this:
YOUR_GITHUB_UN="<your GitHub username>"
git clone --depth 1 "git@github.com:${YOUR_GITHUB_UN}/postgres-operator-examples.git"
cd postgres-operator-examples
Step 2: Install PGO, the Postgres Operator
You can install PGO, the Postgres Operator from Crunchy Data, using the command below:
kubectl apply -k kustomize/install
This will create a namespace called postgres-operator
and create all of the objects required to deploy PGO.
To check on the status of your installation, you can run the following command:
kubectl -n postgres-operator get pods \
--selector=postgres-operator.crunchydata.com/control-plane=postgres-operator \
--field-selector=status.phase=Running
If the PGO Pod is healthy, you should see output similar to:
NAME READY STATUS RESTARTS AGE
postgres-operator-9dd545d64-t4h8d 1/1 Running 0 3s
Create a Postgres Cluster
Let’s create a simple Postgres cluster. You can do this by executing the following command:
kubectl apply -k kustomize/postgres
This will create a Postgres cluster named hippo
in the postgres-operator
namespace. You can track the progress of your cluster using the following command:
kubectl -n postgres-operator describe postgresclusters.postgres-operator.crunchydata.com hippo
Connect to the Postgres cluster
As part of creating a Postgres cluster, the Postgres Operator creates a PostgreSQL user account. The credentials for this account are stored in a Secret that has the name <clusterName>-pguser-<userName>
.
Within this Secret are attributes that provide information to let you log into the PostgreSQL cluster. These include:
user
: The name of the user account.password
: The password for the user account.dbname
: The name of the database that the user has access to by default.host
: The name of the host of the database. This references the Service of the primary Postgres instance.port
: The port that the database is listening on.uri
: A PostgreSQL connection URI that provides all the information for logging into the Postgres database.jdbc-uri
: A PostgreSQL JDBC connection URI that provides all the information for logging into the Postgres database via the JDBC driver.
If you deploy your Postgres cluster with the PgBouncer connection pooler, there are additional values that are populated in the user Secret, including:
pgbouncer-host
: The name of the host of the PgBouncer connection pooler. This references the Service of the PgBouncer connection pooler.pgbouncer-port
: The port that the PgBouncer connection pooler is listening on.pgbouncer-uri
: A PostgreSQL connection URI that provides all the information for logging into the Postgres database via the PgBouncer connection pooler.pgbouncer-jdbc-uri
: A PostgreSQL JDBC connection URI that provides all the information for logging into the Postgres database via the PgBouncer connection pooler using the JDBC driver.
Note that all connections use TLS. PGO sets up a PKI for your Postgres clusters. You can also choose to bring your own PKI / certificate authority; this is covered later in the documentation.
Connect via psql
in the Terminal
Connect Directly
If you are on the same network as your PostgreSQL cluster, you can connect directly to it using the following command:
psql $(kubectl -n postgres-operator get secrets hippo-pguser-hippo -o go-template='{{.data.uri | base64decode}}')
Connect Using a Port-Forward
In a new terminal, create a port forward:
PG_CLUSTER_PRIMARY_POD=$(kubectl get pod -n postgres-operator -o name \
-l postgres-operator.crunchydata.com/cluster=hippo,postgres-operator.crunchydata.com/role=master)
kubectl -n postgres-operator port-forward "${PG_CLUSTER_PRIMARY_POD}" 5432:5432
Establish a connection to the PostgreSQL cluster.
PG_CLUSTER_USER_SECRET_NAME=hippo-pguser-hippo
PGPASSWORD=$(kubectl get secrets -n postgres-operator "${PG_CLUSTER_USER_SECRET_NAME}" -o go-template='{{.data.password | base64decode}}') \
PGUSER=$(kubectl get secrets -n postgres-operator "${PG_CLUSTER_USER_SECRET_NAME}" -o go-template='{{.data.user | base64decode}}') \
PGDATABASE=$(kubectl get secrets -n postgres-operator "${PG_CLUSTER_USER_SECRET_NAME}" -o go-template='{{.data.dbname | base64decode}}') \
psql -h localhost
Connect an Application
The information provided in the user Secret will allow you to connect an application directly to your PostgreSQL database.
For example, let’s connect Keycloak. Keycloak is a popular open source identity management tool that is backed by a PostgreSQL database. Using the hippo
cluster we created, we can deploy the following manifest file:
cat <<EOF >> keycloak.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
name: keycloak
namespace: postgres-operator
labels:
app.kubernetes.io/name: keycloak
spec:
selector:
matchLabels:
app: keycloak
template:
metadata:
labels:
app.kubernetes.io/name: keycloak
spec:
containers:
- image: quay.io/keycloak/keycloak:latest
name: keycloak
env:
- name: DB_VENDOR
value: "postgres"
- name: DB_ADDR
valueFrom: { secretKeyRef: { name: hippo-pguser-hippo, key: host } }
- name: DB_PORT
valueFrom: { secretKeyRef: { name: hippo-pguser-hippo, key: port } }
- name: DB_DATABASE
valueFrom: { secretKeyRef: { name: hippo-pguser-hippo, key: dbname } }
- name: DB_USER
valueFrom: { secretKeyRef: { name: hippo-pguser-hippo, key: user } }
- name: DB_PASSWORD
valueFrom: { secretKeyRef: { name: hippo-pguser-hippo, key: password } }
- name: KEYCLOAK_USER
value: "admin"
- name: KEYCLOAK_PASSWORD
value: "admin"
- name: PROXY_ADDRESS_FORWARDING
value: "true"
ports:
- name: http
containerPort: 8080
- name: https
containerPort: 8443
readinessProbe:
httpGet:
path: /auth/realms/master
port: 8080
restartPolicy: Always
EOF
kubectl apply -f keycloak.yaml
There is a full example for how to deploy Keycloak with the Postgres Operator in the kustomize/keycloak
folder.
Next Steps
Congratulations, you’ve got your Postgres cluster up and running, perhaps with an application connected to it! 👏 👏 👏
You can find out more about the postgresclusters
custom resource definition through the documentation and through kubectl explain
, i.e:
kubectl explain postgresclusters
Let’s work through a tutorial together to better understand the various components of PGO, the Postgres Operator, and how you can fine tune your settings to tailor your Postgres cluster to your application.