目录
一、资源管理介绍
- 资源管理介绍
- 资源管理方式
- 命令式对象管理(只用命令)
- 命令式对象配置(命令+yaml文件)
- 声明式对象配置(apply命令+yaml文件)
二、操作资源命令练习
- Namespace
- 查看命名空间
- 创建、删除命名空间(命令操作、配置操作)
- Pod
- 创建pod并运行
- 查看pod信息
- 访问pod
- 删除pod
- Label
- 命令方式操作
- 配置方式操作
- Deployment
- 命令方式操作
- 配置方式操作
- Service
- 创建集群内部可以访问的Service
- 创建集群外部可以访问的Service
- 删除Service
- 配置方式
一、资源管理
1、资源管理介绍
在kubernetes中,所有的内容都抽象为资源,类似Java中的一切皆对象,用户需要通过操作资源来管理kubernetes。
- kubernetes的本质上就是一个集群系统,用户可以在集群中部署各种服务,所谓的部署服务,其实就是在kubernetes集群中运行一个个的容器,并将指定的程序跑在容器中。可以理解为容器编排。
- kubernetes的最小管理单元是
pod
而不是容器,所以只能将容器放在Pod
中,而kubernetes一般也不会直接管理Pod,而是通过Pod控制器
来管理Pod的。 - Pod可以提供服务之后,就要考虑如何访问Pod中服务,kubernetes提供了
Service
资源实现这个功能。 - 当然,如果Pod中程序的数据需要持久化,kubernetes还提供了各种
存储
系统。
2、资源管理方式
-
命令式对象管理:直接使用命令去操作kubernetes资源
kubectl run nginx-pod --image=nginx:1.17.1 --port=80
-
命令式对象配置:通过命令配置和配置文件去操作kubernetes资源
kubectl create/patch -f nginx-pod.yaml
-
声明式对象配置:通过apply命令和配置文件去操作kubernetes资源
kubectl apply -f nginx-pod.yaml
类型 | 操作对象 | 适用环境 | 优点 | 缺点 |
---|
命令式对象管理 | 对象 | 测试 | 简单 | 只能操作活动对象,无法审计、跟踪 |
命令式对象配置 | 文件 | 开发 | 可以审计、跟踪 | 项目大时,配置文件多,操作麻烦 |
声明式对象配置 | 目录 | 开发 | 支持目录操作 | 意外情况下难以调试 |
2.1命令式对象管理(只用命令)
kubectl命令
kubectl是kubernetes集群的命令行工具,通过它能够对集群本身进行管理,并能够在集群上进行容器化应用的安装部署。kubectl命令的语法如下:kubectl [command] [type] [name] [flags]
kubectl get pod
kubectl get pod pod_name
kubectl get pod pod_name -o yaml
资源类型
kubernetes中所有的内容都抽象为资源,可以通过下面的命令进行查看:kubectl api-resources
,经常使用的资源有下面这些:
资源分类 | 资源名称 | 缩写 | 资源作用 |
---|
集群级别资源 | nodes | no | 集群组成部分 |
namespaces | ns | 隔离Pod | |
pod资源 | pods | po | 装载容器 |
pod资源控制器 | replicationcontrollers | rc | 控制pod资源 |
| replicasets | rs | 控制pod资源 |
| deployments | deploy | 控制pod资源 |
| daemonsets | ds | 控制pod资源 |
| jobs | | 控制pod资源 |
| cronjobs | cj | 控制pod资源 |
| horizontalpodautoscalers | hpa | 控制pod资源 |
| statefulsets | sts | 控制pod资源 |
服务发现资源 | services | svc | 统一pod对外接口 |
| ingress | ing | 统一pod对外接口 |
存储资源 | volumeattachments | | 存储 |
| persistentvolumes | pv | 存储 |
| persistentvolumeclaims | pvc | 存储 |
配置资源 | configmaps | cm | 配置 |
| secrets | | 配置 |
操作
kubernetes允许对资源进行多种操作,可以通过–help查看详细的操作命令:kubectl --help
。经常使用的操作有下面这些:
命令分类 | 命令 | 翻译 | 命令作用 |
---|
基本命令 | create | 创建 | 创建一个资源 |
| edit | 编辑 | 编辑一个资源 |
| get | 获取 | 获取一个资源 |
| patch | 更新 | 更新一个资源 |
| delete | 删除 | 删除一个资源 |
| explain | 解释 | 展示资源文档 |
运行和调试 | run | 运行 | 在集群中运行一个指定的镜像 |
| expose | 暴露 | 暴露资源为Service |
| describe | 描述 | 显示资源内部信息 |
| logs | 日志输出容器在 pod 中的日志 | 输出容器在 pod 中的日志 |
| attach | 缠绕进入运行中的容器 | 进入运行中的容器 |
| exec | 执行容器中的一个命令 | 执行容器中的一个命令 |
| cp | 复制 | 在Pod内外复制文件 |
| rollout | 首次展示 | 管理资源的发布 |
| scale | 规模 | 扩(缩)容Pod的数量 |
| autoscale | 自动调整 | 自动调整Pod的数量 |
高级命令 | apply | rc | 通过文件对资源进行配置 |
| label | 标签 | 更新资源上的标签 |
其他命令 | cluster-info | 集群信息 | 显示集群信息 |
| version | 版本 | 显示当前Server和Client的版本 |
举栗
[root@kubertenes-master ~]
NAME STATUS AGE
default Active 21h
kube-node-lease Active 21h
kube-public Active 21h
kube-system Active 21h
[root@kubertenes-master ~]
namespace/dev created
[root@kubertenes-master ~]
NAME STATUS AGE
default Active 21h
dev Active 2s
kube-node-lease Active 21h
kube-public Active 21h
kube-system Active 21h
[root@kubertenes-master ~]
[root@kubertenes-master ~]
NAME READY STATUS RESTARTS AGE
nginx-6867cdf567-mb2dg 1/1 Running 1 20h
[root@kubertenes-master ~]
kubectl run --generator=deployment/apps.v1 is DEPRECATED and will be removed in a future version. Use kubectl run --generator=run-pod/v1 or kubectl create instead.
deployment.apps/pod created
[root@kubertenes-master ~]
NAME READY STATUS RESTARTS AGE
nginx-6867cdf567-mb2dg 1/1 Running 1 20h
[root@kubertenes-master ~]
NAME READY STATUS RESTARTS AGE
pod-644584df94-8jnkw 1/1 Running 0 4m
[root@kubertenes-master ~]
[root@kubertenes-master ~]
Error from server (NotFound): pods "pod-644584df94-8jnkw" not found
[root@kubertenes-master ~]
pod "pod-644584df94-8jnkw" deleted
[root@kubertenes-master ~]
[root@kubertenes-master ~]
namespace "dev" deleted
[root@kubertenes-master ~]
2.2命令式对象配置(命令+yaml文件)
命令式对象配置就是使用命令配合配置文件一起来操作kubernetes资源。
1) 创建一个nginxpod.yaml,内容如下:
apiVersion: v1
kind: Namespace
metadata:
name: dev
---
apiVersion: v1
kind: Pod
metadata:
name: nginxpod
namespace: dev
spec:
containers:
- name: nginx-containers
image: nginx:latest
2)执行create命令,创建资源:
[root@master ~]
namespace/dev created
pod/nginxpod created
此时发现创建了两个资源对象,分别是namespace和pod
3)执行get命令,查看资源:
[root@master ~]
NAME STATUS AGE
namespace/dev Active 18s
NAME READY STATUS RESTARTS AGE
pod/nginxpod 1/1 Running 0 17s
这样就显示了两个资源对象的信息
4)执行delete命令,删除资源:
[root@master ~]
namespace "dev" deleted
pod "nginxpod" deleted
此时发现两个资源对象被删除了
[root@kubertenes-master ~]
[root@kubertenes-master ~]
namespace/dev created
pod/nginxpod created
[root@kubertenes-master ~]
NAME STATUS AGE
namespace/dev Active 15s
NAME READY STATUS RESTARTS AGE
pod/nginxpod 1/1 Running 0 15s
[root@kubertenes-master ~]
namespace "dev" deleted
pod "nginxpod" deleted
[root@kubertenes-master ~]
总结:命令式对象配置的方式操作资源,可以简单的认为:命令 + yaml配置文件(里面是命令需要的各种参数)
2.3声明式对象配置(apply命令+yaml文件)
声明式对象配置跟命令式对象配置很相似,但是它只有一个命令apply。
[root@kubertenes-master ~]
namespace/dev created
pod/nginxpod created
[root@kubertenes-master ~]
namespace/dev unchanged
pod/nginxpod unchanged
[root@kubertenes-master ~]
总结:
其实声明式对象配置就是使用apply描述一个资源最终的状态(在yaml中定义状态)
使用apply操作资源:
如果资源不存在,就创建,相当于 kubectl create
如果资源已存在,就更新,相当于 kubectl patch
扩展:kubectl可以在node节点上运行吗 ?
kubectl的运行是需要进行配置的,它的配置文件是$HOME/.kube,如果想要在node节点运行此命令,需要将master上的.kube文件复制到node节点上,即在master节点上执行下面操作:scp -r HOME/.kube node1: HOME/
使用推荐: 三种方式应该怎么用 ?
创建/更新资源 使用声明式对象配置 kubectl apply -f XXX.yaml
删除资源 使用命令式对象配置 kubectl delete -f XXX.yaml
查询资源 使用命令式对象管理 kubectl get(describe) 资源名称
二、操作资源命令练习
1、Namespace
Namespace是kubernetes系统中的一种非常重要资源,它的主要作用是用来实现多套环境的资源隔离
-
默认情况下,kubernetes集群中的所有的Pod都是可以相互访问的。但是在实际中,可能不想让两个Pod之间进行互相的访问,那此时就可以将两个Pod划分到不同的namespace下。kubernetes通过将集群内部的资源分配到不同的Namespace中,可以形成逻辑上的"组",以方便不同的组的资源进行隔离使用和管理。
-
可以通过kubernetes的授权机制,将不同的namespace交给不同租户进行管理,这样就实现了多租户的资源隔离。此时还能结合kubernetes的资源配额机制,限定不同租户能占用的资源,例如CPU使用量、内存使用量等等,来实现租户可用资源的管理。
kubernetes在集群启动之后,会默认创建几个namespace
[root@kubertenes-master ~]
NAME STATUS AGE
default Active 24h
dev Active 159m
kube-node-lease Active 24h
kube-public Active 24h
kube-system Active 24h
[root@kubertenes-master ~]
(1) 查看命名空间
[root@kubertenes-master ~]
NAME STATUS AGE
default Active 24h
dev Active 159m
kube-node-lease Active 24h
kube-public Active 24h
kube-system Active 24h
[root@kubertenes-master ~]
NAME STATUS AGE
default Active 24h
[root@kubertenes-master ~]
apiVersion: v1
kind: Namespace
metadata:
creationTimestamp: "2022-05-14T05:45:11Z"
name: default
resourceVersion: "144"
selfLink: /api/v1/namespaces/default
uid: ee758ec0-2154-44ec-82fb-850c66b47c41
spec:
finalizers:
- kubernetes
status:
phase: Active
[root@kubertenes-master ~]
Name: default
Labels: <none>
Annotations: <none>
Status: Active
No resource quota.
No LimitRange resource.
(2) 创建、删除命名空间(命令操作、配置方式操作)
[root@kubertenes-master ~]
namespace/dev-test created
[root@kubertenes-master ~]
namespace "dev-test" deleted
[root@kubertenes-master ~]
apiVersion: v1
kind: Namespace
metadata:
name: dev
[root@kubertenes-master ~]
namespace/dev created
[root@kubertenes-master ~]
NAME STATUS AGE
default Active 24h
dev Active 16s
kube-node-lease Active 24h
kube-public Active 24h
kube-system Active 24h
[root@kubertenes-master ~]
namespace "dev" deleted
[root@kubertenes-master ~]
2、Pod
Pod是kubernetes集群进行管理的最小单元,程序要运行必须部署在容器中,而容器必须存在于Pod中。Pod可以认为是容器的封装,一个Pod中可以存在一个或者多个容器。
kubernetes在集群启动之后,集群中的各个组件也都是以Pod方式运行的。可以通过下面命令查看kube-system
命名空间下的Pod:
[root@kubertenes-master ~]
NAME READY STATUS RESTARTS AGE
coredns-9d85f5447-5ssp5 1/1 Running 2 25h
coredns-9d85f5447-t6ckm 1/1 Running 2 25h
etcd-kubertenes-master 1/1 Running 2 25h
kube-apiserver-kubertenes-master 1/1 Running 2 25h
kube-controller-manager-kubertenes-master 1/1 Running 2 25h
kube-flannel-ds-2k8dm 1/1 Running 3 24h
kube-flannel-ds-68v7z 1/1 Running 2 24h
kube-flannel-ds-zwbpm 1/1 Running 2 24h
kube-proxy-4mtmt 1/1 Running 2 24h
kube-proxy-759s2 1/1 Running 2 24h
kube-proxy-xgwqr 1/1 Running 2 25h
kube-scheduler-kubertenes-master 1/1 Running 2 25h
(1)创建并运行
kubernetes没有提供单独运行Pod的命令,都是通过Pod控制器来实现的
[root@master ~]
deployment.apps/nginx created
(2)查看pod信息
[root@kubertenes-master ~]
NAME STATUS AGE
default Active 25h
kube-node-lease Active 25h
kube-public Active 25h
kube-system Active 25h
[root@kubertenes-master ~]
namespace/dev created
[root@kubertenes-master ~]
NAME STATUS AGE
default Active 25h
dev Active 3s
kube-node-lease Active 25h
kube-public Active 25h
kube-system Active 25h
[root@kubertenes-master ~]
No resources found in dev namespace.
[root@kubertenes-master ~]
kubectl run --generator=deployment/apps.v1 is DEPRECATED and will be removed in a future version. Use kubectl run --generator=run-pod/v1 or kubectl create instead.
deployment.apps/nginx created
[root@kubertenes-master ~]
NAME READY STATUS RESTARTS AGE
nginx-dd6b5d745-gjvr2 1/1 Running 0 7m34s
[root@kubertenes-master ~]
Name: nginx-dd6b5d745-gjvr2
Namespace: dev
Priority: 0
Node: kubernetes-node2/192.168.24.202
Start Time: Sun, 15 May 2022 14:59:20 +0800
Labels: pod-template-hash=dd6b5d745
run=nginx
Annotations: <none>
Status: Running
IP: 10.244.2.12
IPs:
IP: 10.244.2.12
Controlled By: ReplicaSet/nginx-dd6b5d745
Containers:
nginx:
Container ID: docker://4c092841768dc214c599ece15cddd3f721edbc8b6c1bd321d19a34fabc46de86
Image: nginx:latest
Image ID: docker-pullable://nginx@sha256:2c72b42c3679c1c819d46296c4e79e69b2616fa28bea92e61d358980e18c9751
Port: 80/TCP
Host Port: 0/TCP
State: Running
Started: Sun, 15 May 2022 14:59:38 +0800
Ready: True
Restart Count: 0
Environment: <none>
Mounts:
/var/run/secrets/kubernetes.io/serviceaccount from default-token-7t4qr (ro)
Conditions:
Type Status
Initialized True
Ready True
ContainersReady True
PodScheduled True
Volumes:
default-token-7t4qr:
Type: Secret (a volume populated by a Secret)
SecretName: default-token-7t4qr
Optional: false
QoS Class: BestEffort
Node-Selectors: <none>
Tolerations: node.kubernetes.io/not-ready:NoExecute for 300s
node.kubernetes.io/unreachable:NoExecute for 300s
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Normal Scheduled 7m29s default-scheduler Successfully assigned dev/nginx-dd6b5d745-gjvr2 to kubernetes-node2
Normal Pulling 7m18s kubelet, kubernetes-node2 Pulling image "nginx:latest"
Normal Pulled 7m10s kubelet, kubernetes-node2 Successfully pulled image "nginx:latest"
Normal Created 7m10s kubelet, kubernetes-node2 Created container nginx
Normal Started 7m10s kubelet, kubernetes-node2 Started container nginx
(3)访问pod
[root@kubertenes-master ~]
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
nginx-dd6b5d745-gjvr2 1/1 Running 0 12m 10.244.2.12 kubernetes-node2 <none> <none>
[root@kubertenes-master ~]
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
html { color-scheme: light dark; }
body { width: 35em; margin: 0 auto;
font-family: Tahoma, Verdana, Arial, sans-serif; }
</style>
</head>
<body>
<h1>Welcome to nginx!</h1>
<p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p>
<p>For online documentation and support please refer to
<a href="http://nginx.org/">nginx.org</a>.<br/>
Commercial support is available at
<a href="http://nginx.com/">nginx.com</a>.</p>
<p><em>Thank you for using nginx.</em></p>
</body>
</html>
[root@kubertenes-master ~]
(4)删除指定pod
注意:删除pod需要删除对应的pod控制器deploy
[root@kubertenes-master ~]
NAME READY STATUS RESTARTS AGE
nginx-dd6b5d745-gjvr2 1/1 Running 0 17m
[root@kubertenes-master ~]
pod "nginx-dd6b5d745-gjvr2" deleted
[root@kubertenes-master ~]
NAME READY STATUS RESTARTS AGE
nginx-dd6b5d745-t9h5z 0/1 ContainerCreating 0 12s
[root@kubertenes-master ~]
NAME READY UP-TO-DATE AVAILABLE AGE
nginx 0/1 1 0 18m
[root@kubertenes-master ~]
deployment.apps "nginx" deleted
[root@kubertenes-master ~]
No resources found in dev namespace.
[root@kubertenes-master ~]
(5)配置操作
[root@kubertenes-master ~]
apiVersion: v1
kind: Pod
metadata:
name: nginx
namespace: dev
spec:
containers:
- image: nginx:latest
name: pod
ports:
- name: nginx-port
containerPort: 80
protocol: TCP
[root@kubertenes-master ~]
pod/nginx created
[root@kubertenes-master ~]
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
nginx 1/1 Running 0 3m37s 10.244.2.13 kubernetes-node2 <none> <none>
[root@kubertenes-master ~]
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
html { color-scheme: light dark; }
body { width: 35em; margin: 0 auto;
font-family: Tahoma, Verdana, Arial, sans-serif; }
</style>
</head>
<body>
<h1>Welcome to nginx!</h1>
<p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p>
<p>For online documentation and support please refer to
<a href="http://nginx.org/">nginx.org</a>.<br/>
Commercial support is available at
<a href="http://nginx.com/">nginx.com</a>.</p>
<p><em>Thank you for using nginx.</em></p>
</body>
</html>
[root@kubertenes-master ~]
[root@kubertenes-master ~]
pod "nginx" deleted
[root@kubertenes-master ~]
No resources found in dev namespace.
[root@kubertenes-master ~]
3、Label
Label是kubernetes系统中的一个重要概念。它的作用就是在资源上添加标识,用来对它们进行区分和选择。Label的特点:
- 一个Label会以key/value键值对的形式附加到各种对象上,如Node、Pod、Service等等
- 一个资源对象可以定义任意数量的Label ,同一个Label也可以被添加到任意数量的资源对象上去
- Label通常在资源对象定义时确定,当然也可以在对象创建后动态添加或者删除
可以通过Label实现资源的多维度分组,以便灵活、方便地进行资源分配、调度、配置、部署等管理工作。
一些常用的Label 示例如下:
- 版本标签:“version”:“release”, “version”:“stable”…
- 环境标签:“environment”:“dev”,“environment”:“test”,“environment”:“pro”
- 架构标签:“tier”:“frontend”,“tier”:“backend”
当前有两种Label Selector:
- 基于等式的Label Selector
name = slave
: 选择所有包含Label中key="name"且value="slave"的对象
env != production
: 选择所有包括Label中的key="env"且value不等于"production"的对象 - 基于集合的Label Selector
name in (master, slave)
: 选择所有包含Label中的key="name"且value="master"或"slave"的对象
name not in (frontend)
: 选择所有包含Label中的key="name"且value不等于"frontend"的对象
标签定义完毕之后,还要考虑到标签的选择,这就要使用到Label Selector,即:
- Label用于给某个资源对象定义标识
- Label Selector用于查询和筛选拥有某些标签的资源对象
标签的选择条件可以使用多个,此时将多个Label Selector进行组合,使用逗号","进行分隔即可。例如:
- name=slave,env!=production
- name not in (frontend),env!=production
(1) 命令方式
[root@kubertenes-master ~]
NAME READY STATUS RESTARTS AGE
nginx 1/1 Running 0 54s
[root@kubertenes-master ~]
pod/nginx labeled
[root@kubertenes-master ~]
pod/nginx labeled
[root@kubertenes-master ~]
NAME READY STATUS RESTARTS AGE LABELS
nginx 1/1 Running 0 2m12s version=2.0
[root@kubertenes-master ~]
NAME READY STATUS RESTARTS AGE LABELS
nginx 1/1 Running 0 2m59s version=2.0
[root@kubertenes-master ~]
No resources found in dev namespace.
[root@kubertenes-master ~]
pod/nginx labeled
[root@kubertenes-master ~]
NAME READY STATUS RESTARTS AGE LABELS
nginx 1/1 Running 0 4m28s <none>
[root@kubertenes-master ~]
(2) 配置方式
[root@kubertenes-master ~]
apiVersion: v1
kind: Pod
metadata:
name: nginx
namespace: dev
labels:
version: "3.0"
env: "test"
spec:
containers:
- image: nginx:latest
name: pod
ports:
- name: nginx-port
containerPort: 80
protocol: TCP
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pod/nginx created
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NAME READY STATUS RESTARTS AGE LABELS
nginx 0/1 ContainerCreating 0 8s env=test,version=3.0
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4、Deployment
在kubernetes中,Pod是最小的控制单元,但是kubernetes很少直接控制Pod,一般都是通过Pod控制器来完成的。Pod控制器用于pod的管理,确保pod资源符合预期的状态,当pod的资源出现故障时,会尝试进行重启或重建pod。
在kubernetes中Pod控制器的种类有很多,本章节只介绍一种:Deployment。
(1)命令方式
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kubectl run --generator=deployment/apps.v1 is DEPRECATED and will be removed in a future version. Use kubectl run --generator=run-pod/v1 or kubectl create instead.
deployment.apps/nginx created
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NAME READY STATUS RESTARTS AGE
nginx-dd6b5d745-b9zn6 1/1 Running 0 114s
nginx-dd6b5d745-ds75l 1/1 Running 0 114s
nginx-dd6b5d745-r9l8t 0/1 ImagePullBackOff 0 114s
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Name: nginx-dd6b5d745-r9l8t
Namespace: dev
Priority: 0
Node: kubernetes-node1/192.168.24.201
Start Time: Sun, 15 May 2022 16:18:33 +0800
Labels: pod-template-hash=dd6b5d745
run=nginx
Annotations: <none>
Status: Pending
IP: 10.244.1.14
IPs:
IP: 10.244.1.14
Controlled By: ReplicaSet/nginx-dd6b5d745
Containers:
nginx:
Container ID:
Image: nginx:latest
Image ID:
Port: 80/TCP
Host Port: 0/TCP
State: Waiting
Reason: ImagePullBackOff
Ready: False
Restart Count: 0
Environment: <none>
Mounts:
/var/run/secrets/kubernetes.io/serviceaccount from default-token-7t4qr (ro)
Conditions:
Type Status
Initialized True
Ready False
ContainersReady False
PodScheduled True
Volumes:
default-token-7t4qr:
Type: Secret (a volume populated by a Secret)
SecretName: default-token-7t4qr
Optional: false
QoS Class: BestEffort
Node-Selectors: <none>
Tolerations: node.kubernetes.io/not-ready:NoExecute for 300s
node.kubernetes.io/unreachable:NoExecute for 300s
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Normal Scheduled 8m42s default-scheduler Successfully assigned dev/nginx-dd6b5d745-r9l8t to kubernetes-node1
Warning Failed 4m21s kubelet, kubernetes-node1 Failed to pull image "nginx:latest": rpc error: code = Unknown desc = error pulling image configuration: Get https://production.cloudflare.docker.com/registry-v2/docker/registry/v2/blobs/sha256/74/7425d3a7c478efbeb75f0937060117343a9a510f72f5f7ad9f14b1501a36940c/data?verify=1652605944-%2BXlmn7SpGTHeYEkX28CH3CWk58A%3D: dial tcp 104.18.124.25:443: i/o timeout
Warning Failed 3m25s kubelet, kubernetes-node1 Failed to pull image "nginx:latest": rpc error: code = Unknown desc = error pulling image configuration: Get https://production.cloudflare.docker.com/registry-v2/docker/registry/v2/blobs/sha256/74/7425d3a7c478efbeb75f0937060117343a9a510f72f5f7ad9f14b1501a36940c/data?verify=1652606000-fkfR5dGKFdekvuwV5Ul2UE9yrT0%3D: dial tcp 104.18.122.25:443: i/o timeout
Warning Failed 85s kubelet, kubernetes-node1 Failed to pull image "nginx:latest": rpc error: code = Unknown desc = context canceled
Normal BackOff 56s (x4 over 4m20s) kubelet, kubernetes-node1 Back-off pulling image "nginx:latest"
Warning Failed 56s (x4 over 4m20s) kubelet, kubernetes-node1 Error: ImagePullBackOff
Normal Pulling 43s (x4 over 8m41s) kubelet, kubernetes-node1 Pulling image "nginx:latest"
Warning Failed 6s (x4 over 4m21s) kubelet, kubernetes-node1 Error: ErrImagePull
Warning Failed 6s kubelet, kubernetes-node1 Failed to pull image "nginx:latest": rpc error: code = Unknown desc = error pulling image configuration: Get https://production.cloudflare.docker.com/registry-v2/docker/registry/v2/blobs/sha256/74/7425d3a7c478efbeb75f0937060117343a9a510f72f5f7ad9f14b1501a36940c/data?verify=1652606199-V3rHrimE%2BxCIeocPzIbq3dSULUs%3D: dial tcp 104.18.123.25:443: i/o timeout
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NAME READY UP-TO-DATE AVAILABLE AGE
nginx 2/3 3 2 3m23s
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NAME READY UP-TO-DATE AVAILABLE AGE CONTAINERS IMAGES SELECTOR
nginx 2/3 3 2 3m42s nginx nginx:latest run=nginx
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Name: nginx
Namespace: dev
CreationTimestamp: Sun, 15 May 2022 16:18:33 +0800
Labels: run=nginx
Annotations: deployment.kubernetes.io/revision: 1
Selector: run=nginx
Replicas: 3 desired | 3 updated | 3 total | 2 available | 1 unavailable
StrategyType: RollingUpdate
MinReadySeconds: 0
RollingUpdateStrategy: 25% max unavailable, 25% max surge
Pod Template:
Labels: run=nginx
Containers:
nginx:
Image: nginx:latest
Port: 80/TCP
Host Port: 0/TCP
Environment: <none>
Mounts: <none>
Volumes: <none>
Conditions:
Type Status Reason
---- ------ ------
Available False MinimumReplicasUnavailable
Progressing True ReplicaSetUpdated
OldReplicaSets: <none>
NewReplicaSet: nginx-dd6b5d745 (3/3 replicas created)
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Normal ScalingReplicaSet 4m4s deployment-controller Scaled up replica set nginx-dd6b5d745 to 3
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node1节点docker拉取nginx失败443,查看原因
kubernetes-node1 Failed to pull image "nginx:latest":
rpc error: code = Unknown desc = error pulling image configuration:
Get https://production.cloudflare.docker.com/registry-v2/docker/registry/v2/blobs/sha256/74/7425d3a7c478efbeb75f0937060117343a9a510f72f5f7ad9f14b1501a36940c/data?verify=1652605944-%2BXlmn7SpGTHeYEkX28CH3CWk58A%3D: dial tcp 104.18.124.25:443: i/o timeout
解决报错之后
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NAME READY STATUS RESTARTS AGE
nginx-dd6b5d745-8cphw 1/1 Running 0 9m54s
nginx-dd6b5d745-s6g4w 1/1 Running 0 9m54s
nginx-dd6b5d745-vb5w6 1/1 Running 0 9m54s
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NAME READY UP-TO-DATE AVAILABLE AGE
nginx 3/3 3 3 43s
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NAME READY UP-TO-DATE AVAILABLE AGE CONTAINERS IMAGES SELECTOR
nginx 3/3 3 3 58s nginx nginx:latest run=nginx
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Name: nginx
Namespace: dev
CreationTimestamp: Sun, 15 May 2022 16:59:04 +0800
Labels: run=nginx
Annotations: deployment.kubernetes.io/revision: 1
Selector: run=nginx
Replicas: 3 desired | 3 updated | 3 total | 3 available | 0 unavailable
StrategyType: RollingUpdate
MinReadySeconds: 0
RollingUpdateStrategy: 25% max unavailable, 25% max surge
Pod Template:
Labels: run=nginx
Containers:
nginx:
Image: nginx:latest
Port: 80/TCP
Host Port: 0/TCP
Environment: <none>
Mounts: <none>
Volumes: <none>
Conditions:
Type Status Reason
---- ------ ------
Available True MinimumReplicasAvailable
Progressing True NewReplicaSetAvailable
OldReplicaSets: <none>
NewReplicaSet: nginx-dd6b5d745 (3/3 replicas created)
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Normal ScalingReplicaSet 100s deployment-controller Scaled up replica set nginx-dd6b5d745 to 3
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deployment.apps "nginx" deleted
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(2)配置方式
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apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx
namespace: dev
spec:
replicas: 3
selector:
matchLabels:
run: nginx
template:
metadata:
labels:
run: nginx
spec:
containers:
- image: nginx:latest
name: nginx
ports:
- containerPort: 80
protocol: TCP
[root@kubertenes-master ~]
deployment.apps/nginx created
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NAME READY UP-TO-DATE AVAILABLE AGE
nginx 3/3 3 3 33s
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deployment.apps "nginx" deleted
5、 Service
通过上面Pod的操作,已经能够利用Deployment来创建一组Pod来提供具有高可用性的服务。虽然每个Pod都会分配一个单独的Pod IP,然而却存在如下两问题:
- Pod IP 会随着Pod的重建产生变化
- Pod IP 仅仅是集群内可见的虚拟IP,外部无法访问
这样对于访问这个服务带来了难度。因此,kubernetes设计了Service来解决这个问题。
Service可以看作是一组同类Pod对外的访问接口。借助Service,应用可以方便地实现服务发现和负载均衡。
(1) 创建集群内部可访问的Service
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deployment.apps/nginx created
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NAME READY UP-TO-DATE AVAILABLE AGE
nginx 3/3 3 3 32s
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service/svc-nginx1 exposed
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NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR
svc-nginx1 ClusterIP 10.101.198.180 <none> 80/TCP 25s run=nginx
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<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
html { color-scheme: light dark; }
body { width: 35em; margin: 0 auto;
font-family: Tahoma, Verdana, Arial, sans-serif; }
</style>
</head>
<body>
<h1>Welcome to nginx!</h1>
<p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p>
<p>For online documentation and support please refer to
<a href="http://nginx.org/">nginx.org</a>.<br/>
Commercial support is available at
<a href="http://nginx.com/">nginx.com</a>.</p>
<p><em>Thank you for using nginx.</em></p>
</body>
</html>
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(2) 创建集群外部也可访问的Service
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service/svc-nginx2 exposed
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NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR
svc-nginx2 NodePort 10.100.234.127 <none> 80:32688/TCP 8s run=nginx
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浏览器访问:http://kubernetes-master:32688/
(3) 删除Service
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service "svc-nginx1" deleted
(4) 配置方式
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apiVersion: v1
kind: Service
metadata:
name: svc-nginx
namespace: dev
spec:
clusterIP: 10.101.198.180
ports:
- port: 80
protocol: TCP
targetPort: 80
selector:
run: nginx
type: ClusterIP
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service/svc-nginx created
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