📗 프로비저닝 - PostgreSQL

🏳️‍🌈 [궁금한점]

• PostgreSQL 설치 방법 (HostPath 방식)

---

🔗[목차]

• PostgreSQL 설치
  • 1️⃣ 준비
    • PostgreSQL 차트 다운로드
    • StorageClass 작성
    • PV 구성
  • 2️⃣ 설정 - 사용자 Values 파일 생성
  • 3️⃣ 설치 - PostgreSQL 설치
  • 4️⃣ 검증 - 설치 확인

PostgreSQL 설치

1️⃣ 준비

PostgreSQL 차트 다운로드

helm repo add bitnami https://charts.bitnami.com/bitnami
helm repo update

helm pull bitnami/postgresql --untar

cd postgresql

StorageClass 작성

k apply -f mysc.yml

apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
  name: local-storage
provisioner: kubernetes.io/no-provisioner
volumeBindingMode: WaitForFirstConsumer

PV 구성

StorageClass 지정하는 것에 유의한다.

• 디렉토리 생성 (slave1)

sudo mkdir /mnt/data{1..3}

• pv 생성

k apply -f mypv.yml

apiVersion: v1
kind: PersistentVolume
metadata:
  name: mypv1
  labels:
    type: local
spec:
  storageClassName: local-storage
  persistentVolumeReclaimPolicy: Delete
  capacity:
    storage: 2Gi
  accessModes:
    - ReadWriteOnce
  hostPath:
    path: "/mnt/data1"
  nodeAffinity:
    required:
      nodeSelectorTerms:
      - matchExpressions:
        - {key: kubernetes.io/hostname, operator: In, values: [slave1]}     
---
apiVersion: v1
kind: PersistentVolume
metadata:
  name: mypv2
  labels:
    type: local
spec:
  storageClassName: local-storage
  persistentVolumeReclaimPolicy: Delete
  capacity:
    storage: 2Gi
  accessModes:
    - ReadWriteOnce
  hostPath:
    path: "/mnt/data2"
  nodeAffinity:
    required:
      nodeSelectorTerms:
      - matchExpressions:
        - {key: kubernetes.io/hostname, operator: In, values: [slave1]}   
---
apiVersion: v1
kind: PersistentVolume
metadata:
  name: mypv3
  labels:
    type: local
spec:
  storageClassName: local-storage
  persistentVolumeReclaimPolicy: Delete
  capacity:
    storage: 2Gi
  accessModes:
    - ReadWriteOnce
  hostPath:
    path: "/mnt/data3"
  nodeAffinity:
    required:
      nodeSelectorTerms:
      - matchExpressions:
        - {key: kubernetes.io/hostname, operator: In, values: [slave1]}     
---

pv 목록 확인

k get pv

NAME CAPACITY ACCESS MODES RECLAIM POLICY STATUS CLAIM STORAGECLASS REASON AGE
mypv1 2Gi RWO Delete Available local-storage 3s
mypv2 2Gi RWO Delete Available local-storage 3s
mypv3 2Gi RWO Delete Available local-storage 3s

## 2️⃣ 설정 - 사용자 Values 파일 생성
``` bash
cp values.yaml dev-values.yaml

• dev-values.yaml 파일 편집
• 아래 내용 남기고 삭제

global:
  postgresql:
    auth:
      postgresPassword: "psql"
      username: "admin"
      password: "psql"
      database: "psql"
primary:
  persistence:
    size: 2Gi
    storageClass: "local-storage"
readReplicas:
  persistence:
    size: 2Gi
    storageClass: "local-storage"
backup:
  persistence:
    size: 2Gi
    storageClass: "local-storage" 

• value 파일 적용 확인

cd ..
helm template postgresql -f dev-values.yaml

3️⃣ 설치 - PostgreSQL 설치

cd postgresql

helm install mypsql . -n psql --create-namespace -f dev-values.yaml --set volumePermissions.enabled=true

NAME: mypsql
LAST DEPLOYED: Fri May 30 18:06:59 2025
NAMESPACE: psql
STATUS: deployed
REVISION: 1
TEST SUITE: None
NOTES:
CHART NAME: postgresql
CHART VERSION: 16.7.4
APP VERSION: 17.5.0

Did you know there are enterprise versions of the Bitnami catalog? For enhanced secure software supply chain features, unlimited pulls from Docker, LTS support, or application customization, see Bitnami Premium or Tanzu Application Catalog. See https://www.arrow.com/globalecs/na/vendors/bitnami for more information.

** Please be patient while the chart is being deployed **

PostgreSQL can be accessed via port 5432 on the following DNS names from within your cluster:

    mypsql-postgresql.psql.svc.cluster.local - Read/Write connection

To get the password for "postgres" run:

    export POSTGRES_ADMIN_PASSWORD=$(kubectl get secret --namespace psql mypsql-postgresql -o jsonpath="{.data.postgres-password}" | base64 -d)

To get the password for "admin" run:

    export POSTGRES_PASSWORD=$(kubectl get secret --namespace psql mypsql-postgresql -o jsonpath="{.data.password}" | base64 -d)

To connect to your database run the following command:

    kubectl run mypsql-postgresql-client --rm --tty -i --restart='Never' --namespace psql --image docker.io/bitnami/postgresql:17.5.0-debian-12-r3 --env="PGPASSWORD=$POSTGRES_PASSWORD" \
      --command -- psql --host mypsql-postgresql -U admin -d psql -p 5432

    > NOTE: If you access the container using bash, make sure that you execute "/opt/bitnami/scripts/postgresql/entrypoint.sh /bin/bash" in order to avoid the error "psql: local user with ID 1001} does not exist"

To connect to your database from outside the cluster execute the following commands:

    kubectl port-forward --namespace psql svc/mypsql-postgresql 5432:5432 &
    PGPASSWORD="$POSTGRES_PASSWORD" psql --host 127.0.0.1 -U admin -d psql -p 5432

WARNING: The configured password will be ignored on new installation in case when previous PostgreSQL release was deleted through the helm command. In that case, old PVC will have an old password, and setting it through helm won't take effect. Deleting persistent volumes (PVs) will solve the issue.

WARNING: There are "resources" sections in the chart not set. Using "resourcesPreset" is not recommended for production. For production installations, please set the following values according to your workload needs:
  - primary.resources
  - readReplicas.resources
+info https://kubernetes.io/docs/concepts/configuration/manage-resources-containers/

PVC 확인

k get pvc -n psql

NAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS AGE
data-mypsql-postgresql-0 Bound mypv1 2Gi RWO local-storage 30s

>### POD 확인
``` bash
k get po -n psql

NAME                  READY   STATUS    RESTARTS   AGE
mypsql-postgresql-0   1/1     Running   0          42s

pv 패치

helm 을 삭제하고, pvc를 삭제해도 pv에 Released 상태로 남아있으면 정상적으로 bound 되지 않으니 아래처럼 patch 를 해준다.

kubectl patch pv <PV_NAME> -p '{"spec":{"claimRef": null}}'

4️⃣ 검증 - 설치 확인

k exec -it mypsql-postgresql-0 -n psql -- bash

I have no name!@mypsql-postgresql-0:/$I have no name!@mypsql-postgresql-0:/$ psql psql -U admin
Password for user admin:
psql (17.5)
Type "help" for help.

psql=> \c psql
You are now connected to database "psql" as user "admin".

psql=> SELECT current_database();

current_database

psql
(1 row)