kubernetes复制控制器

Question

我有一个简单的kubernetes集群,有一个主人和3个小兵.在这种情况下,如果我运行一个简单的nginx或一个mysql的pod它工作正常,但是,如果我将KIND的类型更改为yaml文件,我尝试运行一个复制的服务,pods将启动但我无法访问服务.

这是我的nginx的yaml文件,包含3个副本:

apiVersion: v1
kind: ReplicationController
metadata:
  name: nginx
spec:
  replicas: 3
  selector:
    app: nginx
  template:
    metadata:
      name: nginx
      labels:
        app: nginx
    spec:
      containers:
      - name: nginx
        image: nginx
        ports:
        - containerPort: 80

这是服务yaml配置文件:

apiVersion: v1
kind: Service
metadata: 
  labels: 
    name: nginx
  name: nginx
spec: 
  ports:
    - port: 80
  selector: 
    name: nginx

我运行它:

# kubectl create -f nginx-rc.yaml
# kubectl create -f nginx-rc-service.yaml

如果我跑:

# kubectl get pod,svc,rc -o wide

我知道了:

NAME          READY     STATUS    RESTARTS   AGE       NODE
nginx-kgq1s   1/1       Running   0          1m        node01
nginx-pomx3   1/1       Running   0          1m        node02
nginx-xi54i   1/1       Running   0          1m        node03
NAME         LABELS                                    SELECTOR     IP(S)                           PORT(S)
kubernetes   component=apiserver,provider=kubernetes   <none>       10.254.0.1      443/TCP
nginx        name=nginx                                name=nginx   10.254.47.150   80/TCP
CONTROLLER   CONTAINER(S)   IMAGE(S)   SELECTOR    REPLICAS
nginx        nginx          nginx      app=nginx   3

我可以看到pod的描述:

Name:                           nginx-kgq1s
Namespace:                      default
Image(s):                       nginx
Node:                           node01/node01
Labels:                         app=nginx
Status:                         Running
Reason:
Message:
IP:                             172.17.52.3
Replication Controllers:        nginx (3/3 replicas created)
Containers:
  nginx:
    Image:              nginx
    State:              Running
      Started:          Thu, 11 Feb 2016 16:28:08 +0100
    Ready:              True
    Restart Count:      0
Conditions:
  Type          Status
  Ready         True 
Events:
  FirstSeen                             LastSeen                        Count   From                            SubobjectPath                           Reason          Message
  Thu, 11 Feb 2016 16:27:47 +0100       Thu, 11 Feb 2016 16:27:47 +0100 1       {scheduler }                                                            scheduled       Successfully assigned nginx-kgq1s to node01
  Thu, 11 Feb 2016 16:27:57 +0100       Thu, 11 Feb 2016 16:27:57 +0100 1       {kubelet node01}        implicitly required container POD       pulled          Pod container image "gcr.io/google_containers/pause:0.8.0" already present on machine
  Thu, 11 Feb 2016 16:28:02 +0100       Thu, 11 Feb 2016 16:28:02 +0100 1       {kubelet node01}        implicitly required container POD       created         Created with docker id bed30a90c6eb
  Thu, 11 Feb 2016 16:28:02 +0100       Thu, 11 Feb 2016 16:28:02 +0100 1       {kubelet node01}        implicitly required container POD       started         Started with docker id bed30a90c6eb
  Thu, 11 Feb 2016 16:28:07 +0100       Thu, 11 Feb 2016 16:28:07 +0100 1       {kubelet node01}        spec.containers{nginx}                  created         Created with docker id 0a5c69cd0481
  Thu, 11 Feb 2016 16:28:08 +0100       Thu, 11 Feb 2016 16:28:08 +0100 1       {kubelet node01}        spec.containers{nginx}                  started         Started with docker id 0a5c69cd0481

如果我得到rc的描述,这就是我所看到的:

Name:           nginx
Namespace:      default
Image(s):       nginx
Selector:       app=nginx
Labels:         app=nginx
Replicas:       3 current / 3 desired
Pods Status:    3 Running / 0 Waiting / 0 Succeeded / 0 Failed
Events:
  FirstSeen                             LastSeen                        Count   From                            SubobjectPath   Reason                  Message
  Thu, 11 Feb 2016 16:27:47 +0100       Thu, 11 Feb 2016 16:27:47 +0100 1       {replication-controller }                       successfulCreate        Created pod: nginx-kgq1s
  Thu, 11 Feb 2016 16:27:47 +0100       Thu, 11 Feb 2016 16:27:47 +0100 1       {replication-controller }                       successfulCreate        Created pod: nginx-pomx3
  Thu, 11 Feb 2016 16:27:47 +0100       Thu, 11 Feb 2016 16:27:47 +0100 1       {replication-controller }                       successfulCreate        Created pod: nginx-xi54i

如果我得到服务描述,这就是我所看到的:

Name:                   nginx
Namespace:              default
Labels:                 name=nginx
Selector:               name=nginx
Type:                   ClusterIP
IP:                     10.254.47.150
Port:                   <unnamed>       80/TCP
Endpoints:              <none>
Session Affinity:       None
No events.

正如我所看到的,问题可能是我没有ENDPOINT,但我不知道如何解决.

Answer 1

它看起来像你的服务选择器是错误的.它正在寻找一个标签name: nginx,但你的豆荚实际上有app: nginx.

尝试将您的服务文件更改为:

apiVersion: v1
kind: Service
metadata: 
  labels: 
    name: nginx
  name: nginx
spec: 
  ports:
    - port: 80
  selector: 
    app: nginx

...或更改复制控制器模板以使用name: nginx而不是app: nginx标签.基本上,标签必须匹配,以便服务知道如何在您的pod上呈现统一的外观.