I've just launched a fairly basic cluster based on the CoreOS kube-aws scripts.

https://coreos.com/kubernetes/docs/latest/kubernetes-on-aws.html

I've activated the registry add-on, and I have it correctly proxying to my local box so I can push images to the cluster on localhost:5000. I also have the proxy pod correctly loaded on each node so that localhost:5000 will also pull images from that registry.

https://github.com/kubernetes/kubernetes/tree/master/cluster/addons/registry

Then I dockerized a fairly simple Sinatra app to run on my cluster and pushed it to the registry. I also prepared a ReplicationController definition and Service definition to run the app. The images pulled and started no problem, I can use kubectl to get the startup logs from each pod that belongs to the replication group.

My problem is that when I curl the public ELB endpoint for my service, it just hangs.

Things I've tried:

• I got the public IP for one of the nodes running my pod and attempted to curl it at the NodePort described in the service description, same thing.
• I SSH'd into that node and attempted curl localhost:3000, same result.
• Also SSH'd into that node, I attempted to curl <pod-ip>:3000, same result.
• ps shows the Puma process running and listening on port 3000.
• docker ps on the node shows that the app container is not forwarding any ports to the host. Is that maybe the problem?

The requests must be routing correctly because hitting those IPs at any other port results in a connection refused rather than hanging.

The Dockerfile for my app is fairly straightforward:

FROM ruby:2.2.4-onbuild
RUN apt-get update -qq && apt-get install -y \
  libpq-dev \
  postgresql-client

RUN mkdir -p /app
WORKDIR /app

COPY . /app

EXPOSE 3000

ENTRYPOINT ['ruby', '/app/bin/entrypoint.rb']

Where entrypoint.rb will start a Puma server listening on port 3000.

My replication group is defined like so:

apiVersion: v1
kind: ReplicationController
metadata:
  name: web-controller
  namespace: app
spec:
  replicas: 2
  selector:
    app: web
  template:
    metadata:
      labels:
        app: web
    spec:
      volumes:
      - name: secrets
        secret:
          secretName: secrets
      containers:
      - name: app
        image: localhost:5000/app:v2
        resources:
          limits:
            cpu: 100m
            memory: 50Mi
        env:
        - name: DATABASE_NAME
          value: app_production
        - name: DATABASE_URL
          value: postgresql://some.postgres.aws.com:5432
        - name: ENV
          value: production
        - name: REDIS_URL
          value: redis://some.redis.aws.com:6379
        volumeMounts:
        - name: secrets
          mountPath: "/etc/secrets"
          readOnly: true
        command: ['/app/bin/entrypoint.rb', 'web']
        ports:
          - containerPort: 3000

And here is my service:

apiVersion: v1
kind: Service
metadata:
  name: web-service
spec:
  ports:
  - port: 80
    targetPort: 3000
    protocol: TCP
  selector:
    app: web
  type: LoadBalancer

Output of kubectl describe service web-service:

Name:           web-service
Namespace:      app
Labels:         <none>
Selector:       app=web
Type:           LoadBalancer
IP:         10.3.0.204
LoadBalancer Ingress:   some.elb.aws.com
Port:           <unnamed>   80/TCP
NodePort:       <unnamed>   32062/TCP
Endpoints:      10.2.47.3:3000,10.2.73.3:3000
Session Affinity:   None
No events.

docker ps on one of the nodes shows that the app container is not forwarding any ports to the host. Is that maybe the problem?

Edit to add entrypoint.rb and Procfile

entrypoint.rb:

#!/usr/bin/env ruby

db_user_file = '/etc/secrets/database_user'
db_password_file = '/etc/secrets/database_password'

ENV['DATABASE_USER'] = File.read(db_user_file) if File.exists?(db_user_file)
ENV['DATABASE_PASSWORD'] = File.read(db_password_file) if File.exists?(db_password_file)

exec("bundle exec foreman start #{ARGV[0]}")

Procfile:

web: PORT=3000 bundle exec puma
message_worker: bundle exec sidekiq -q messages -c 1 -r ./config/environment.rb
email_worker: bundle exec sidekiq -q emails -c 1 -r