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kubernetes 1.3.0 run-stateless-application-deployment

15 Jan 2018

0. Objectives

deployment(nginx) 创建；
deployment信息查看(kubectl)；
deployment 更新。

参考链接：kubenetes 官方文档

执行以下操作之前，可以参照文档先创建一个kubenetes cluster

1. Creating and exploring an nginx deployment

deployment.yaml

apiVersion: apps/v1beta2 # for versions before 1.8.0 use apps/v1beta1
kind: Deployment
metadata:
  name: nginx-deployment
spec:
  selector:
    matchLabels:
      app: nginx
  replicas: 2 # tells deployment to run 2 pods matching the template
  template: # create pods using pod definition in this template
    metadata:
      # unlike pod-nginx.yaml, the name is not included in the meta data as a unique name is
      # generated from the deployment name
      labels:
        app: nginx
    spec:
      containers:
      - name: nginx
        image: nginx:1.7.9
        ports:
        - containerPort: 80

1) 创建deploment

kubectl apply -f https://k8s.io/docs/tasks/run-application/deployment.yaml

2) 查看deploment

kubectl describe deployment nginx-deployment

输出结果

Name:                   nginx-deployment
Namespace:              default
CreationTimestamp:      Mon, 15 Jan 2018 06:19:34 +0000
Labels:                 app=nginx
Annotations:            deployment.kubernetes.io/revision=1
                        kubectl.kubernetes.io/last-applied-configuration={"apiVersion":"apps/v1beta2","kind":"Deployment","metadata":{"annotations":{},"name":"nginx-deployment","namespace":"default"},"spec":{"replicas":2,"se...
Selector:               app=nginx
Replicas:               2 desired | 2 updated | 2 total | 0 available | 2 unavailable
StrategyType:           RollingUpdate
MinReadySeconds:        0
RollingUpdateStrategy:  25% max unavailable, 25% max surge
Pod Template:
  Labels:  app=nginx
  Containers:
   nginx:
    Image:        nginx:1.7.9
    Port:         80/TCP
    Environment:  <none>
    Mounts:       <none>
  Volumes:        <none>
Conditions:
  Type           Status  Reason
  ----           ------  ------
  Available      False   MinimumReplicasUnavailable
  Progressing    True    ReplicaSetUpdated
OldReplicaSets:  <none>
NewReplicaSet:   nginx-deployment-6c54bd5869 (2/2 replicas created)
Events:
  Type    Reason             Age   From                   Message
  ----    ------             ----  ----                   -------
  Normal  ScalingReplicaSet  15m   deployment-controller  Scaled up replica set nginx-deployment-6c54bd5869 to 2

3) 查看pods

kubectl get pods -l app=nginx

输出结果

NAME                                READY     STATUS    RESTARTS   AGE
nginx-deployment-6c54bd5869-f56kg   1/1       Running   0          16m
nginx-deployment-6c54bd5869-p79hd   1/1       Running   0          16m

4) 查看pod详细信息

kubectl describe pod nginx-deployment-6c54bd5869-f56kg

输出结果

Name:           nginx-deployment-6c54bd5869-f56kg
Namespace:      default
Node:           node01/10.0.2.15
Start Time:     Mon, 15 Jan 2018 07:00:55 +0000
Labels:         app=nginx
                pod-template-hash=2710681425
Annotations:    <none>
Status:         Running
IP:             10.5.52.3
Controlled By:  ReplicaSet/nginx-deployment-6c54bd5869
Containers:
  nginx:
    Container ID:   docker://cf62a29a203a6870fa8a8fc0610835cb16e53bd31a30d2c75a734b59ced355b5
    Image:          nginx:1.7.9
    Image ID:       docker-pullable://nginx@sha256:e3456c851a152494c3e4ff5fcc26f240206abac0c9d794affb40e0714846c451
    Port:           80/TCP
    State:          Running
      Started:      Mon, 15 Jan 2018 07:02:32 +0000
    Ready:          True
    Restart Count:  0
    Environment:    <none>
    Mounts:         <none>
Conditions:
  Type           Status
  Initialized    True
  Ready          True
  PodScheduled   True
Volumes:         <none>
QoS Class:       BestEffort
Node-Selectors:  <none>
Tolerations:     <none>
Events:
  Type     Reason             Age                 From               Message
  ----     ------             ----                ----               -------
  Warning  FailedScheduling   26m (x26 over 33m)  default-scheduler  0/3 nodes are available: 3 NodeNotReady.
  Normal   Scheduled          22m                 default-scheduler  Successfully assigned nginx-deployment-6c54bd5869-f56kg to node01
  Normal   Pulling            22m                 kubelet, node01    pulling image "nginx:1.7.9"
  Normal   Pulled             21m                 kubelet, node01    Successfully pulled image "nginx:1.7.9"
  Normal   Created            21m                 kubelet, node01    Created container
  Normal   Started            21m                 kubelet, node01    Started container
  Warning  MissingClusterDNS  1m (x20 over 22m)   kubelet, node01    pod: "nginx-deployment-6c54bd5869-f56kg_default(65c64d74-f9c0-11e7-a243-525400cae48b)". kubelet does not have ClusterDNS IP configured and cannot create Pod using "ClusterFirst" policy. Falling back to "Default" policy.

2. Updating the deployment

升级nginx到1.8,deployment-update.yaml

apiVersion: apps/v1beta2 # for versions before 1.8.0 use apps/v1beta1
kind: Deployment
metadata:
  name: nginx-deployment
spec:
  selector:
    matchLabels:
      app: nginx
  replicas: 2
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
      - name: nginx
        image: nginx:1.8 # Update the version of nginx from 1.7.9 to 1.8
        ports:
        - containerPort: 80

1) apply新的deploment

kubectl apply -f https://k8s.io/docs/tasks/run-application/deployment-update.yaml

2) 查看pod更新过程

kubectl get pods -l app=nginx

输出结果

NAME                                READY     STATUS              RESTARTS   AGE
nginx-deployment-6c54bd5869-f56kg   1/1       Running             0          37m
nginx-deployment-6c54bd5869-p79hd   1/1       Running             0          37m
nginx-deployment-7694d679d9-z5fdf   0/1       ContainerCreating   0          40s

查看正在创建的pod的状态

kubectl describe pod nginx-deployment-7694d679d9-z5fdf

输出结果

Name:           nginx-deployment-7694d679d9-z5fdf
Namespace:      default
Node:           node03/10.0.2.15
Start Time:     Mon, 15 Jan 2018 07:27:08 +0000
Labels:         app=nginx
                pod-template-hash=3250823585
Annotations:    <none>
Status:         Pending
IP:             
Controlled By:  ReplicaSet/nginx-deployment-7694d679d9
Containers:
  nginx:
    Container ID:   
    Image:          nginx:1.8
    Image ID:       
    Port:           80/TCP
    State:          Waiting
      Reason:       ContainerCreating
    Ready:          False
    Restart Count:  0
    Environment:    <none>
    Mounts:         <none>
Conditions:
  Type           Status
  Initialized    True
  Ready          False
  PodScheduled   True
Volumes:         <none>
QoS Class:       BestEffort
Node-Selectors:  <none>
Tolerations:     <none>
Events:
  Type     Reason             Age                From               Message
  ----     ------             ----               ----               -------
  Normal   Scheduled          53s                default-scheduler  Successfully assigned nginx-deployment-7694d679d9-z5fdf to node03
  Warning  MissingClusterDNS  51s (x2 over 53s)  kubelet, node03    pod: "nginx-deployment-7694d679d9-z5fdf_default(7e34acdf-f9c5-11e7-a243-525400cae48b)". kubelet does not have ClusterDNS IP configured and cannot create Pod using "ClusterFirst" policy. Falling back to "Default" policy.
  Normal   Pulling            51s                kubelet, node03    pulling image "nginx:1.8"

正在pull nginx1.8的镜像

k8s已经创建了新的pod，杀死了一个pod

kubectl get pods -l app=nginx

输出结果

NAME                                READY     STATUS              RESTARTS   AGE
nginx-deployment-6c54bd5869-f56kg   1/1       Running             0          40m
nginx-deployment-7694d679d9-4465x   0/1       ContainerCreating   0          1m
nginx-deployment-7694d679d9-z5fdf   1/1       Running             0          3m

最终会创建两个新的pod，所有旧的pod被杀死

kubectl get pods -l app=nginx

NAME                                READY     STATUS    RESTARTS   AGE
nginx-deployment-7694d679d9-4465x   1/1       Running   0          2m
nginx-deployment-7694d679d9-z5fdf   1/1       Running   0          5m

查看新的deployment

kubectl describe deployment nginx-deployment

输出结果中能很清晰的看到更新过程

Name:                   nginx-deployment
Namespace:              default
CreationTimestamp:      Mon, 15 Jan 2018 06:50:37 +0000
Labels:                 app=nginx
Annotations:            deployment.kubernetes.io/revision=2
                        kubectl.kubernetes.io/last-applied-configuration={"apiVersion":"apps/v1beta2","kind":"Deployment","metadata":{"annotations":{},"name":"nginx-deployment","namespace":"default"},"spec":{"replicas":2,"se...
Selector:               app=nginx
Replicas:               2 desired | 2 updated | 2 total | 2 available | 0 unavailable
StrategyType:           RollingUpdate
MinReadySeconds:        0
RollingUpdateStrategy:  25% max unavailable, 25% max surge
Pod Template:
  Labels:  app=nginx
  Containers:
   nginx:
    Image:        nginx:1.8
    Port:         80/TCP
    Environment:  <none>
    Mounts:       <none>
  Volumes:        <none>
Conditions:
  Type           Status  Reason
  ----           ------  ------
  Available      True    MinimumReplicasAvailable
  Progressing    True    NewReplicaSetAvailable
OldReplicaSets:  <none>
NewReplicaSet:   nginx-deployment-7694d679d9 (2/2 replicas created)
Events:
  Type    Reason             Age   From                   Message
  ----    ------             ----  ----                   -------
  Normal  ScalingReplicaSet  42m   deployment-controller  Scaled up replica set nginx-deployment-6c54bd5869 to 2
  Normal  ScalingReplicaSet  6m    deployment-controller  Scaled up replica set nginx-deployment-7694d679d9 to 1
  Normal  ScalingReplicaSet  3m    deployment-controller  Scaled down replica set nginx-deployment-6c54bd5869 to 1
  Normal  ScalingReplicaSet  3m    deployment-controller  Scaled up replica set nginx-deployment-7694d679d9 to 2
  Normal  ScalingReplicaSet  55s   deployment-controller  Scaled down replica set nginx-deployment-6c54bd5869 to 0

3. Scaling the application by increasing the replica count

修改replicas为4

apiVersion: apps/v1beta2 # for versions before 1.8.0 use apps/v1beta1
kind: Deployment
metadata:
  name: nginx-deployment
spec:
  selector:
    matchLabels:
      app: nginx
  replicas: 4 # Update the replicas from 2 to 4
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
      - name: nginx
        image: nginx:1.8
        ports:
        - containerPort: 80

1) apply新的deploment

kubectl apply -f https://k8s.io/docs/tasks/run-application/deployment-scale.yaml

2) 查看更新结果

kubectl get pods -l app=nginx

输出结果

NAME                                READY     STATUS    RESTARTS   AGE
nginx-deployment-7694d679d9-4465x   1/1       Running   0          10m
nginx-deployment-7694d679d9-ncg7f   1/1       Running   0          2m
nginx-deployment-7694d679d9-skxr9   1/1       Running   0          2m
nginx-deployment-7694d679d9-z5fdf   1/1       Running   0          13m

4. Deleting a deployment

kubectl delete deployment nginx-deployment

最新文章

文章分类

kubernetes 1.3.0 run-stateless-application-deployment

0. Objectives

1. Creating and exploring an nginx deployment

1) 创建deploment

2) 查看deploment

3) 查看pods

4) 查看pod详细信息

2. Updating the deployment

1) apply新的deploment

2) 查看pod更新过程

3. Scaling the application by increasing the replica count

1) apply新的deploment

2) 查看更新结果

4. Deleting a deployment