Kubernetes how to access a service from another namespace

Question

I'm using https://github.com/Yolean/kubernetes-kafka to run kubernetes on minikube I exposed an outside port and successfully used producers and consumers from outside the cluster

➜  ~ kubectl get svc --namespace kafka
NAME        TYPE        CLUSTER-IP       EXTERNAL-IP   PORT(S)                     
AGE
bootstrap   ClusterIP   10.108.21.84     <none>        9092/TCP            
1h
broker      ClusterIP   None             <none>        9092/TCP            
1h
outside-0   NodePort    10.99.182.13     <none>        32400:32400/TCP     
1h
outside-1   NodePort    10.108.10.223    <none>        32401:32401/TCP     
1h
outside-2   NodePort    10.101.155.122   <none>        32402:32402/TCP     
1h
pzoo        ClusterIP   None             <none>        2888/TCP,3888/TCP   
1h
zoo         ClusterIP   None             <none>        2888/TCP,3888/TCP   
1h
zookeeper   ClusterIP   10.97.17.36      <none>        2181/TCP            
1h

python producer

from kafka import KafkaConsumer, KafkaProducer

KAFKA_TOPIC = 'demo'
KAFKA_BROKERS = '192.168.99.100:32400' # see step 1

producer = KafkaProducer(bootstrap_servers=KAFKA_BROKERS)

messages = [b'hello kafka', b'Falanga', b'3 test messages']


for m in messages:
    print(f"sending: {m}")
    producer.send(KAFKA_TOPIC, m)

producer.flush()

Simple consumer

#!/usr/bin/env python

from kafka import KafkaConsumer

KAFKA_TOPIC = 'demo'
KAFKA_BROKERS = '192.168.99.100:32400' # see step 1

consumer = KafkaConsumer(KAFKA_TOPIC, bootstrap_servers=KAFKA_BROKERS)

for message in consumer:
    print(f"message is of type: {type(message)}")
    print(message)

print('yo')
consumer.subscribe([KAFKA_TOPIC])

How do I access the service from pods in 'default' namespace by name not using the out facing url?

Answer 1

You can access to the Service in the pod using the following ways.

• Using the env variables,

  https://kubernetes.io/docs/concepts/services-networking/service/#discovering-services

• Using internal service name, i.e.> YOURSERVICENAME.NAMESPACE.svc.cluster.local

  https://kubernetes.io/docs/concepts/services-networking/dns-pod-service/#services