I have a deployment of a simple Django app in minikube. It has two containers one for the Django app and one for postgres db. It is working with docker-compose, but couldn't make it work in minikube k8s cluster. When I opened a terminal to the container and ping the service it wasn't successful. I didn't find what causes this communication error.
It's a basic app that just has a login page for signing in or signing up. After signing in you can create some notes. After I deployed to minikube I was able to access 127.0.0.1:8000, but when I enter the information to sign up it gave the error below. Apparently, it couldn't store data in the db.
DATABASES part in settings.py in django project:
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.postgresql_psycopg2',
'NAME': 'postgres',
'USER': 'postgres',
'PASSWORD': 'postgres',
'HOST': 'db',
'PORT': '5432',
}
}
Dockerfile for building the image for the app:
FROM python:2.7
WORKDIR /notejam
COPY ./ ./
RUN pip install -r requirements.txt
EXPOSE 8000
CMD python manage.py runserver 0.0.0.0:8000
Deployment file:
apiVersion: apps/v1
kind: Deployment
metadata:
name: notejam-deployment
labels:
app: notejam-app
spec:
selector:
matchLabels:
app: notejam-app
template:
metadata:
labels:
app: notejam-app
spec:
volumes:
- name: postgres-pvc
persistentVolumeClaim:
claimName: postgres-pvc
containers:
- name: notejam
image: notejam_k8s
imagePullPolicy: Never
resources:
limits:
memory: "128Mi"
cpu: "500m"
ports:
- containerPort: 8000
- name: postgres-db
image: postgres
imagePullPolicy: Never
ports:
- containerPort: 5432
resources:
limits:
memory: "128Mi"
cpu: "500m"
env:
- name: POSTGRES_USERNAME
valueFrom:
configMapKeyRef:
name: postgres-configmap
key: postgres-username
- name: POSTGRES_PASSWORD
valueFrom:
secretKeyRef:
name: postgres-secret
key: postgres-password
- name: POSTGRES_DB
valueFrom:
configMapKeyRef:
name: postgres-configmap
key: postgres-db
volumeMounts:
- mountPath: /notejam-db
name: postgres-pvc
---
apiVersion: v1
kind: Service
metadata:
name: db
spec:
selector:
app: notejam-app
ports:
- port: 5432
targetPort: 5432
---
apiVersion: v1
kind: Service
metadata:
name: notejam-external-service
spec:
selector:
app: notejam-app
type: LoadBalancer
ports:
- protocol: TCP
port: 8000
targetPort: 8000
Error:
OperationalError at /signup/
could not connect to server: Connection timed out
Is the server running on host "db" (10.96.150.207) and accepting
TCP/IP connections on port 5432?
Request Method: POST
Request URL: http://127.0.0.1:8000/signup/
Django Version: 1.6.5
Exception Type: OperationalError
Exception Value:
could not connect to server: Connection timed out
Is the server running on host "db" (10.96.150.207) and accepting
TCP/IP connections on port 5432?
Exception Location: /usr/local/lib/python2.7/site-packages/psycopg2/__init__.py in connect, line 127
Python Executable: /usr/local/bin/python
Python Version: 2.7.18
Python Path:
['/notejam',
'/usr/local/lib/python27.zip',
'/usr/local/lib/python2.7',
'/usr/local/lib/python2.7/plat-linux2',
'/usr/local/lib/python2.7/lib-tk',
'/usr/local/lib/python2.7/lib-old',
'/usr/local/lib/python2.7/lib-dynload',
'/usr/local/lib/python2.7/site-packages']
Server time: Thu, 26 Aug 2021 00:40:58 +0300
