GKE pods not connecting to Cloudsql - kubernetes

Question

My app can't seem to connect to the proxy thus my Cloudsql Database.
Below are my setup:
my-simple-app.yaml
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
labels:
name: web
name: web
spec:
replicas: 2
selector:
matchLabels:
name: web
strategy:
type: RollingUpdate
rollingUpdate:
maxSurge: 1
maxUnavailable: 1
minReadySeconds: 5
template:
metadata:
labels:
name: web
spec:
nodeSelector:
cloud.google.com/gke-nodepool: default-pool
containers:
- image: joelaw/nameko-hello:0.2
name: web
env:
- name: DB_HOST
value: 127.0.0.1
- name: DB_PASSWORD
valueFrom:
secretKeyRef:
name: cloudsql-db-credentials
key: password
- name: DB_USER
valueFrom:
secretKeyRef:
name: cloudsql-db-credentials
key: username
ports:
- containerPort: 3000
name: http-server
- image: gcr.io/cloudsql-docker/gce-proxy:1.09
name: cloudsql-proxy
command: ["/cloud_sql_proxy", "--dir=/cloudsql",
"-instances=spheric-veric-task:asia-southeast1:authdb:5432",
"-credential_file=/secrets/cloudsql/credentials.json"]
volumeMounts:
- name: cloudsql-instance-credentials
mountPath: /secrets/cloudsql
readOnly: true
- name: ssl-certs
mountPath: /etc/ssl/certs
- name: cloudsql
mountPath: /cloudsql
volumes:
- name: cloudsql-instance-credentials
secret:
secretName: cloudsql-instance-credentials
- name: ssl-certs
hostPath:
path: /etc/ssl/certs
- name: cloudsql
emptyDir:
I had setup the secrets correctly I suppose.
Below are some data that I collected from the instance:
The pod live happily:
web-69c7777c68-s2jt6 2/2 Running 0 9m
web-69c7777c68-zbwtv 2/2 Running 0 9m
When I run: kubectl logs web-69c7777c68-zbwtv -c cloudsql-proxy
It recorded this:
2019/04/04 03:25:35 using credential file for authentication; email=auth-db-user#spheric-verve-228610.iam.gserviceaccount.com
2019/04/04 03:25:35 Listening on /cloudsql/spheric-veric-task:asia-southeast1:authdb:5432/.s.PGSQL.5432 for spheric-veric-task:asia-southeast1:authdb:5432
2019/04/04 03:25:35 Ready for new connections
Since the app is not configured to connect to the db, what I did is to ssh into the pod with:
kubectl exec -it web-69c7777c68-mrdpn -- /bin/bash
# Followed by installing postgresql driver:
apt-get install postgresql
# Trying to connect to cloudsql:
psql -h 127.0.0.1 -p 5432 -U
When I run psql in the container:
psql: could not connect to server: Connection refused
Is the server running on host "127.0.0.1" and accepting
TCP/IP connections on port 5432?
Can anyone of you kindly advise what should I do to connect to the DB?

Answer 1

You are specifying the instance connection string wrong, and so the proxy is listening on a unix socket in the /cloudsql/ directory instead of to a TCP port.
To tell the proxy to listen on a TCP port, use the following:
-instances=<INSTANCE_CONNECTION_NAME>=tcp:5432
Otherwise, the following format creates a unix socket (defaulting to the /cloudsql directory):
-instances=<INSTANCE_CONNECTION_NAME>