Implementation Goal
Expose Zookeeper instance, running on kubernetes, to the internet.
(configuration & version information provided at the bottom)
Implementation Attempt
I currently have a minikube
cluster running on ubuntu 14.04
, backed by docker
containers.
I'm running a bare metal k8s cluster, and I'm trrying to expose a zookeeper service to the internet. Seeing as my cluster is not running on a cloud provider, I set up metallb
, in order to provide a network-loadbalancer implementation for my zookeeper service.
On startup everything looks good, an external IP is assigned and I can access it from the same host via a curl command.
$ kubectl get pods -n metallb-system
NAME READY STATUS RESTARTS AGE
controller-5c9894b5cd-9gh8m 1/1 Running 0 5h59m
speaker-j2z8q 1/1 Running 0 5h59m
$ kubectl get svc
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kubernetes ClusterIP 10.xxx.xxx.xxx <none> 443/TCP 6d19h
zk-cs LoadBalancer 10.xxx.xxx.xxx 172.1.1.x 2181:30035/TCP 56m
zk-hs LoadBalancer 10.xxx.xxx.xxx 172.1.1.x 2888:30664/TCP,3888:31113/TCP 6m15s
When I curl the above mentioned external IP's, I get a valid response
$ curl -D- "http://172.1.1.x:2181"
curl: (52) Empty reply from server
So far it all looks good, I can access the LB from outside the cluster with no issues, but this is where my lack of Kubernetes/Networking knowledge gets me.I'm finding it impossible to expose this LB to the internet. I've tried running minikube tunnel
which I had high hopes for, only to be deeply disappointed.
Running a curl command from another node, whilst minikube tunnel is running will just see the request time out.
$ curl -D- "http://172.1.1.x:2181"
curl: (28) Failed to connect to 172.1.1.x port 2181: Timed out
At this point, as I mentioned before, I'm stuck.
Is there any way that I can get this service exposed to the internet without giving my soul to AWS
or GCP
?
Any help will be greatly appreciated.
Service Configuration
apiVersion: v1
kind: Service
metadata:
name: zk-hs
labels:
app: zk
spec:
selector:
app: zk
ports:
- port: 2888
targetPort: 2888
name: server
protocol: TCP
- port: 3888
targetPort: 3888
name: leader-election
protocol: TCP
clusterIP: ""
type: LoadBalancer
---
apiVersion: v1
kind: Service
metadata:
name: zk-cs
labels:
app: zk
spec:
selector:
app: zk
ports:
- name: client
protocol: TCP
port: 2181
targetPort: 2181
type: LoadBalancer
---
apiVersion: policy/v1beta1
kind: PodDisruptionBudget
metadata:
name: zk-pdb
spec:
selector:
matchLabels:
app: zk
maxUnavailable: 1
---
apiVersion: apps/v1
kind: StatefulSet
metadata:
name: zk
spec:
selector:
matchLabels:
app: zk
serviceName: zk-hs
replicas: 1
updateStrategy:
type: RollingUpdate
podManagementPolicy: OrderedReady
template:
metadata:
labels:
app: zk
spec:
affinity:
podAntiAffinity:
requiredDuringSchedulingIgnoredDuringExecution:
- labelSelector:
matchExpressions:
- key: "app"
operator: In
values:
- zk
topologyKey: "kubernetes.io/hostname"
containers:
- name: zookeeper
imagePullPolicy: Always
image: "library/zookeeper:3.6"
resources:
requests:
memory: "1Gi"
cpu: "0.5"
ports:
- containerPort: 2181
name: client
- containerPort: 2888
name: server
- containerPort: 3888
name: leader-election
volumeMounts:
- name: datadir
mountPath: /var/lib/zookeeper
- name: zoo-config
mountPath: /conf
volumes:
- name: zoo-config
configMap:
name: zoo-config
securityContext:
fsGroup: 2000
runAsUser: 1000
runAsNonRoot: true
volumeClaimTemplates:
- metadata:
name: datadir
spec:
accessModes: [ "ReadWriteOnce" ]
resources:
requests:
storage: 10Gi
---
apiVersion: v1
kind: ConfigMap
metadata:
name: zoo-config
namespace: default
data:
zoo.cfg: |
tickTime=10000
dataDir=/var/lib/zookeeper
clientPort=2181
initLimit=10
syncLimit=4
apiVersion: v1
kind: ConfigMap
metadata:
namespace: metallb-system
name: config
data:
config: |
address-pools:
- name: default
protocol: layer2
addresses:
- 172.1.1.1-172.1.1.10
minikube: v1.13.1
docker: 18.06.3-ce