Cannot access a Kubernetes postgresql service from the outside - postgresql

Question

I'm using Docker 1.10.1 and Kubernetes 1.0.1 on a local bare metal computer with Ubuntu 14.04, and I'm still new on this.
That computer is the Kubernetes master as well as the node I'm using to make tests (I'm currently making a proof of concept).
I created a couple of containers (1 nginx and 1 postgresql 9.2) to play with them.
I created the service and pod definitions for the postgresql container as follows:
----- app-postgres-svc.yaml
apiVersion: v1
kind: Service
metadata:
labels:
name: AppPostgres
name: app-postgres
spec:
ports:
- port: 5432
selector:
app: AppPostgresPod
type: NodePort
clusterIP: 192.168.3.105
----- app-postgres-pod.yaml
apiVersion: v1
kind: ReplicationController
metadata:
name: app-postgres-pod
spec:
replicas: 1
selector:
app: AppPostgresPod
template:
metadata:
name: app-postgres-pod
labels:
app: AppPostgresPod
spec:
containers:
- name: app-postgres-pod
image: localhost:5000/app_postgres
ports:
- containerPort: 5432
I also installed HAProxy in order to redirect the requests to ports 80 and 5432 to their corresponding Kubernetes service.
The following is the HAProxy definition of the frontend and backend for the postgresql redirection:
frontend postgres
bind *:5432
mode tcp
option tcplog
default_backend postgres-kubernetes
backend postgres-kubernetes
mode tcp
balance roundrobin
option pgsql-check
server postgres-01 192.168.3.105:5432 check
After I start the kubernetes cluster, services and pods, I first tried hitting the nginx site from the outside and it works like
a charm. But, when I try to connect to the postgresql service from the outside I get the following error:
Error connecting to the server: server closed the connection unexpectedly
This probably means the server terminated abnormally before or while processing the request.
And if I look at the log, there are too many of these messages:
LOG: incomplete startup packet
LOG: incomplete startup packet
...
This is the command I use to try to connect from the outside (from another computer on the same LAN):
psql -h 192.168.0.100 -p 5432 -U myuser mydb
I also tried using pgAdmin and the same error was displayed.
Note: if I try to connect to the postgres service from the docker/kubernetes host itself, I can connect without any problems:
psql -h 192.168.3.105 -p 5432 -U myuser mydb
So it seems like the Kubernetes portion is working fine.
What might be wrong?
EDIT: including the details of the LAN computers involved in the proof of concept, as well as the kubernetes definitions
for the nginx stuff and the entries on haproxy configuration.
So the issue happens when I try to connect from my laptop to the postgres service on the docker/kubernetes box (I thought HAProxy would redirect the request that arrives to the docker/kubernetes box at port 5432 to the kubernetes postgres service)
----- LAN Network
My Laptop: 192.168.0.5
HAProxy/Docker/Kubernetes box: 192.168.0.100
|
---> Kubernetes Nginx Service: 192.168.3.104
|
---> Nginx Pod: 172.16.4.5
|
---> Kubernetes Postgres Service: 192.168.3.105
|
---> Postgres Pod: 172.16.4.9
----- app-nginx-svc.yaml
apiVersion: v1
kind: Service
metadata:
labels:
name: AppNginx
name: app-nginx
spec:
ports:
- port: 80
selector:
app: AppNginxPod
type: NodePort
clusterIP: 192.168.3.104
----- app-nginx-pod-yaml
apiVersion: v1
kind: ReplicationController
metadata:
name: app-nginx-pod
spec:
replicas: 2
selector:
app: AppNginxPod
template:
metadata:
name: app-nginx-pod
labels:
app: AppNginxPod
spec:
containers:
- name: app-nginx-pod
image: localhost:5000/app_nginx
ports:
- containerPort: 80
----- haproxy entries on /etc/haproxy/haproxy.cfg
frontend nginx
bind *:80
mode http
default_backend nginx-kubernetes
backend nginx-kubernetes
mode http
balance roundrobin
option forwardfor
option http-server-close
http-request set-header X-Forwarded-Port %[dst_port]
http-request add-header X-Forwarded-Proto https if { ssl_fc }
server nginx-01 192.168.3.104:80 check
SOLUTION: I had to specify the user parameter in the pgsql-check line of the HAProxy configuration. After that, I was able to connect without any problems. Went back and removed the user parameter just to verify that the error was back, and it was. So, definitely, the problem was caused by the absence of the user parameter in the pgsql-check line.