Kubernetes：从Pods访问外部系统不起作用

我试图访问 within kubernetes pod（在minikube-VM内）到 external Zookeeper / Kafka（在kubernetes-domain之外），这基本上不起作用 .

首先，我有一个docker-image，它运行一个Spring-Boot应用程序，它试图在启动时连接到端口2181/9092上的Kafka-Instance . 由于我创建了一个带有 endpoints 的服务，它指向应该修复路由的外部主机/ IP，但不幸的是它没有 .

这是服务/ endpoints 的定义

apiVersion: v1
kind: Service
metadata:
  name: ext-kafka
  namespace: default
spec:
  clusterIP: None
  ports:
  - port: 2181
    name: zk
    protocol: TCP
    targetPort: 2181
  - port: 9092
    name: kafka
    protocol: TCP
    targetPort: 9092
---
apiVersion: v1
kind: Endpoints
metadata:
  name: ext-kafka
  namespace: default
subsets:
- addresses:
  # 192.168.99.1 is the external IP
  - ip: 192.168.99.1
  ports:
  - port: 2181
    name: zk
  - port: 9092
    name: kafka


#
# HERE ARE THE DEPLOYMENTS/DEFINITIONS THAT THE SERVICES ARE INSTALLED
#
[root@centos1 work]# kubectl get services
NAME                      CLUSTER-IP   EXTERNAL-IP   PORT(S)             AGE
ext-kafka                 None         <none>        2181/TCP,9092/TCP   2d

 ...

[root@centos1 work]# kubectl get endpoints
NAME                      ENDPOINTS                             AGE
ext-kafka                 192.168.99.1:2181,192.168.99.1:9092   2d

我检查了minikube VM上的iptables，因为它声明包被拒绝了 . 因此，清理不能解决问题，因为它会在幕后自动重建 .

$ iptables -L
....

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination         
KUBE-FIREWALL  all  --  anywhere             anywhere            
KUBE-SERVICES  all  --  anywhere             anywhere             /* kubernetes service portals */

...

Chain KUBE-FIREWALL (2 references)
target     prot opt source               destination         
DROP       all  --  anywhere             anywhere             /* kubernetes firewall for dropping marked packets */ mark match 0x8000/0x8000

Chain KUBE-SERVICES (1 references)
target     prot opt source               destination         
....
REJECT     tcp  --  anywhere             anywhere             /* default/server-command: has no endpoints */ ADDRTYPE match dst-type LOCAL tcp dpt:30021 reject-with icmp-port-unreachable
REJECT     tcp  --  anywhere             10.0.0.240           /* default/server-command: has no endpoints */ tcp dpt:webcache 

....

另一种缓解星座的方法：

我在主机上使用 ncat -l 192.168.99.1 2181 --keep-open 运行ncat，其中zookeeper / Kafka应该运行并尝试从minikube-VM连接到 telnet 192.168.99.1 2181 我得到'no rotue to host' ...

那么如何解决这个问题呢？如何添加解决iptables问题的服务？ （我使用了BuildDate构建的kubernetes：“2017-05-10T15：48：59Z”）

BR