K8S基础搭建使用
一、 K8S架构
除了核心组件，还有一些推荐的Add-ons：
| 组件名称 | 说明 |
|---|---|
| kube-dns | 负责为整个集群提供DNS服务 |
| Ingress Controller | 为服务提供外网入口 |
| Heapster | 提供资源监控 |
| Dashboard | 提供GUI |
| Federation | 提供跨可用区的集群 |
| Fluentd-elasticsearch | 提供集群日志采集、存储与查询 |
K8S核心功能：
- 自愈: 重新启动失败的容器，在节点不可用时，替换和重新调度节点上的容器，对用户定义的健康检查不响应的容器会被中止，并且在容器准备好服务之前不会把其向客户端广播。
- 弹性伸缩: 通过监控容器的cpu的负载值,如果这个平均高于80%,增加容器的数量,如果这个平均低于10%,减少容器的数量
- 服务的自动发现和负载均衡: 不需要修改您的应用程序来使用不熟悉的服务发现机制，Kubernetes 为容器提供了自己的 IP 地址和一组容器的单个 DNS 名称，并可以在它们之间进行负载均衡。
- 滚动升级和一键回滚: Kubernetes 逐渐部署对应用程序或其配置的更改，同时监视应用程序运行状况，以确保它不会同时终止所有实例。 如果出现问题，Kubernetes会为您恢复更改，利用日益增长的部署解决方案的生态系统。
1.1环境准备
cat >> /etc/hosts <<EOF
10.0.0.202 master
10.0.0.215 etcd
10.0.0.197 node1
10.0.0.163 node2
EOF
1.2 etcd节点安装
[root@etcd ~]# yum install etcd -y
vim /etc/etcd/etcd.conf
6行：ETCD_LISTEN_CLIENT_URLS="http://0.0.0.0:2379"
21行：ETCD_ADVERTISE_CLIENT_URLS="http://10.0.0.215:2379"
systemctl start etcd.service
systemctl enable etcd.service
[root@etcd ~]# etcdctl -C http://10.0.0.215:2379 cluster-health
member 8e9e05c52164694d is healthy: got healthy result from http://10.0.0.215:2379
cluster is healthy
1.3 master节点安装：
yum install kubernetes-master.x86_64 -y
vim /etc/kubernetes/apiserver
8行: KUBE_API_ADDRESS="--insecure-bind-address=0.0.0.0"
11行：KUBE_API_PORT="--port=8080"
17行：KUBE_ETCD_SERVERS="--etcd-servers=http://10.0.0.215:2379"
23行：KUBE_ADMISSION_CONTROL="--admission-control=NamespaceLifecycle,NamespaceExists,LimitRanger,SecurityContextDeny,ResourceQuota"
vim /etc/kubernetes/config
22行：KUBE_MASTER="--master=http://10.0.0.202:8080"
systemctl enable kube-apiserver.service
systemctl restart kube-apiserver.service
systemctl enable kube-controller-manager.service
systemctl restart kube-controller-manager.service
systemctl enable kube-scheduler.service
systemctl restart kube-scheduler.service
检查服务是否正常
[root@master ~]# kubectl get componentstatus
NAME STATUS MESSAGE ERROR
scheduler Healthy ok
controller-manager Healthy ok
etcd-0 Healthy {"health":"true"}
1.3 node节点安装
yum install kubernetes-node.x86_64 -y
vim /etc/kubernetes/config
22行：KUBE_MASTER="--master=http://10.0.0.202:8080"
vim /etc/kubernetes/kubelet
5行：KUBELET_ADDRESS="--address=0.0.0.0"
8行：KUBELET_PORT="--port=10250"
11行：KUBELET_HOSTNAME="--hostname-override=10.0.0.163" #node节点ip
14行：KUBELET_API_SERVER="--api-servers=http://10.0.0.202:8080"
17行：KUBELET_POD_INFRA_CONTAINER="--pod-infra-container-image=10.0.0.202:5000/rhel7/pod-infrastructure:latest" #这里需要把pod-infrastructure镜像做到本地镜像仓库
systemctl enable kubelet.service
systemctl restart kubelet.service
systemctl enable kube-proxy.service
systemctl restart kube-proxy.service
在master节点检查
[root@master ~]# kubectl get node
NAME STATUS AGE
10.0.0.163 Ready 1d
10.0.0.197 Ready 1d
1.4 所有节点配置flannel网络
yum install flannel -y
sed -i 's#http://127.0.0.1:2379#http://10.0.0.215:2379#g' /etc/sysconfig/flanneld
##etcd节点：
etcdctl mk /atomic.io/network/config '{ "Network": "172.18.0.0/16" }'
##master节点
yum install docker -y
systemctl enable flanneld.service
systemctl restart flanneld.service
service docker restart
systemctl restart kube-apiserver.service
systemctl restart kube-controller-manager.service
systemctl restart kube-scheduler.service
##node节点：
systemctl enable flanneld.service
systemctl restart flanneld.service
service docker restart
systemctl restart kubelet.service
systemctl restart kube-proxy.service
vim /usr/lib/systemd/system/docker.service
#在[Service]区域下增加一行
ExecStartPost=/usr/sbin/iptables -P FORWARD ACCEPT
systemctl daemon-reload
systemctl restart docker
1.5 配置master为镜像仓库
#所有节点
vim /etc/sysconfig/docker
OPTIONS='--selinux-enabled --log-driver=journald --signature-verification=false --registry-mirror=https://registry.docker-cn.com --insecure-registry=10.0.0.202:5000'
systemctl restart docker
#master节点（如有网络问题，多试几次）
docker run -d -p 5000:5000 --restart=always --name registry -v /opt/myregistry:/var/lib/registry registry
二、 K8S常用资源
2.1 pod资源
pod是最小资源单位.
k8s yaml的主要组成
apiVersion: v1 api版本
kind: pod 资源类型
metadata: 属性
spec: 详细
- 创建一个yaml文件：
[root@master pod]# cat k8s_pod.yaml
apiVersion: v1
kind: Pod
metadata:
name: nginx
labels:
app: web
spec:
containers:
- name: nginx
image: 10.0.0.202:5000/nginx:latest
ports:
- containerPort: 80
基于yaml创建pod：
[root@master pod]# kubectl create -f k8s_pod.yaml
pod "nginx1" created
[root@master pod]# kubectl get pod
NAME READY STATUS RESTARTS AGE
nginx 0/1 ContainerCreating 0 12s
此时发现pod创建没能成功，通过
kubectl describe pod nginx查看详细信息：
Events:
FirstSeen LastSeen Count From SubObjectPath Type Reason Message
--------- -------- ----- ---- ------------- -------- ------ -------
2m 2m 1 {default-scheduler } Normal Scheduled Successfully assigned nginx to 10.0.0.197
2m 43s 4 {kubelet 10.0.0.197} Warning FailedSync Error syncing pod, skipping: failed to "StartContainer" for "POD" with ErrImagePull: "image pull failed for registry.access.redhat.com/rhel7/pod-infrastructure:latest, this may be because there are no credentials on this request. details: (open /etc/docker/certs.d/registry.access.redhat.com/redhat-ca.crt: no such file or directory)"
1m 6s 6 {kubelet 10.0.0.197} Warning FailedSync Error syncing pod, skipping: failed to "StartContainer" for "POD" with ImagePullBackOff: "Back-off pulling image \"registry.access.redhat.com/rhel7/pod-infrastructure:latest\""
由上可见，需要本地镜像仓库需要pod-infrastructure:latest 这个pod基础镜像，所以需要在拉取镜像
docker pull tianyebj/pod-infrastructure，并且push到本地镜像仓库
docker pull tianyebj/pod-infrastructure
docker tag docker.io/tianyebj/pod-infrastructure 10.0.0.202:5000/rhel7/pod-infrastructure:latest
docker push 10.0.0.202:5000/rhel7/pod-infrastructure:latest
#同时改下node节点： /etc/kubernetes/kubelet
#更改配置：KUBELET_POD_INFRA_CONTAINER="--pod-infra-container-image=10.0.0.202:5000/rhel7/pod-infrastructure:latest"
systemctl restart kubelet.service
在此查看pod创建过程：
Events:
FirstSeen LastSeen Count From SubObjectPath Type Reason Message
--------- -------- ----- ---- ------------- -------- ------ -------
14m 14m 1 {default-scheduler } Normal Scheduled Successfully assigned nginx to 10.0.0.197
13m 3m 7 {kubelet 10.0.0.197} Warning FailedSync Error syncing pod, skipping: failed to "StartContainer" for "POD" with ErrImagePull: "image pull failed for registry.access.redhat.com/rhel7/pod-infrastructure:latest, this may be because there are no credentials on this request. details: (open /etc/docker/certs.d/registry.access.redhat.com/redhat-ca.crt: no such file or directory)"
13m 58s 54 {kubelet 10.0.0.197} Warning FailedSync Error syncing pod, skipping: failed to "StartContainer" for "POD" with ImagePullBackOff: "Back-off pulling image \"registry.access.redhat.com/rhel7/pod-infrastructure:latest\""
45s 45s 1 {kubelet 10.0.0.197} spec.containers{nginx} Normal Pulling pulling image "10.0.0.202:5000/nginx:1.13"
46s 41s 2 {kubelet 10.0.0.197} Warning MissingClusterDNS kubelet does not have ClusterDNS IP configured and cannot create Pod using "ClusterFirst" policy. Falling back to DNSDefault policy.
41s 41s 1 {kubelet 10.0.0.197} spec.containers{nginx} Normal Pulled Successfully pulled image "10.0.0.202:5000/nginx:1.13"
41s 41s 1 {kubelet 10.0.0.197} spec.containers{nginx} Normal Created Created container with docker id 9254a49fc62c; Security:[seccomp=unconfined]
41s 41s 1 {kubelet 10.0.0.197} spec.containers{nginx} Normal Started Started container with docker id 9254a49fc62c
到此pod创建完成
详细
在这里需要把pod容器tag改成需要用的：
[root@master pod]# docker tag docker.io/tianyebj/pod-infrastructure 10.0.0.202:5000/rhel7/pod-infrastructure:latest
[root@master pod]# docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
docker.io/registry latest f32a97de94e1 9 months ago 25.8 MB
docker.io/tianyebj/pod-infrastructure latest 34d3450d733b 2 years ago 205 MB
10.0.0.202:5000/rhel7/pod-infrastructure latest 34d3450d733b 2 years ago 205 MB
强制删除pod资源：
[root@master pod]# kubectl delete pod nginx --force --grace-period=0 -n default
warning: Immediate deletion does not wait for confirmation that the running resource has been terminated. The resource may continue to run on the cluster indefinitely.
pod "nginx" deleted
安装docker镜像并且push到本地镜像仓库
[root@master pod]# docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
docker.io/b3log/solo latest 4e49320bec76 2 days ago 152 MB
10.0.0.202:5000/b3log/solo latest 4e49320bec76 2 days ago 152 MB
docker.io/mysql 5.7 1e4405fe1ea9 2 weeks ago 437 MB
10.0.0.202:5000/nginx latest 231d40e811cd 2 weeks ago 126 MB
docker.io/nginx latest 231d40e811cd 2 weeks ago 126 MB
docker.io/registry latest f32a97de94e1 9 months ago 25.8 MB
10.0.0.202:5000/rhel7/pod-infrastructure latest 34d3450d733b 2 years ago 205 MB
docker.io/tianyebj/pod-infrastructure latest 34d3450d733b 2 years ago 205 MB
[root@master pod]# docker tag docker.io/nginx 10.0.0.202:5000/nginx:latest
[root@master pod]# docker push 10.0.0.202:5000/nginx
[root@master pod]# docker tag docker.io/mysql:5.7 10.0.0.202:5000/mysql:5.7
[root@master pod]# docker push 10.0.0.202:5000/mysql
创建pod
[root@master pod]# kubectl create -f k8s_pod.yaml
pod "nginx" created
[root@master pod]# kubectl get pod
NAME READY STATUS RESTARTS AGE
nginx 1/1 Running 0 7s
pod运行多个容器：
[root@master pod]# cat k8s_pod2.yaml
apiVersion: v1
kind: Pod
metadata:
name: test
labels:
app: web
spec:
containers:
- name: nginx
image: 10.0.0.202:5000/nginx:latest
ports:
- containerPort: 80
- name: solo
image: 10.0.0.202:5000/b3log/solo:latest
command: ["sleep","10000"]
[root@master pod]# kubectl create -f k8s_pod2.yaml
pod "test" created
[root@master pod]# kubectl get pod -o wide
NAME READY STATUS RESTARTS AGE IP NODE
nginx 1/1 Running 0 15h 172.18.57.2 10.0.0.197
test 2/2 Running 0 15s 172.18.39.2 10.0.0.163
查看k8s pod的容器资源详细信息：
docker inspect 3f6cdafa32f5
创建一个pod资源，才能实现k8s的高级功能.
pod容器：基础架构容器
nginx容器： 业务容器
[root@node1 ~]# docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
3f6cdafa32f5 10.0.0.202:5000/nginx:latest "nginx -g 'daemon ..." 17 hours ago Up 17 hours k8s_nginx.c74a033c_nginx_default_e5a7a5ea-1bf8-11ea-950d-fa163ef9cf10_5e72b386
d0198f64f479 10.0.0.202:5000/rhel7/pod-infrastructure:latest "/pod" 17 hours ago Up 17 hours k8s_POD.7b6a03f3_nginx_default_e5a7a5ea-1bf8-11ea-950d-fa163ef9cf10_7ee05d13
2.2 ReplicationController资源
k8s资源的常见操作:
kubectl create -f xxx.yaml
kubectl get pod|rc
kubectl describe pod nginx
kubectl delete pod nginx 或者kubectl delete -f xxx.yaml
kubectl edit pod nginx
rc:保证指定数量的pod始终存活,rc通过标签选择器来关联pod
POD资源被关闭也会及时启动自愈。
rc资源
pod资源的高可用行
[root@node2 ~]# docker ps -a -q
f14a9650d408
5a4a70671124
[root@node2 ~]# docker rm -f `docker ps -a -q`
f14a9650d408
5a4a70671124
[root@node2 ~]# docker ps -a -q
7f4142ea7eb9
2ec639b32132
pod资源被强制删除停止后，这些资源会立即重新生成并启动。
rc创建
rc:保证指定数量的pod始终够存活，rc通过标签选择器来关联pod
- 创建yaml文件
[root@master rc]# cat k8s_rc.yaml
apiVersion: v1
kind: ReplicationController
metadata:
name: nginx
spec:
replicas: 5
selector:
app: myweb
template:
metadata:
labels:
app: myweb
spec:
containers:
- name: myweb
image: 10.0.0.202:5000/nginx:1.13
ports:
- containerPort: 80
- 创建rc：
[root@master rc]# pwd
/root/k8s/rc
[root@master rc]# kubectl create -f k8s_rc.yaml
replicationcontroller "nginx" created
查看状态：
[root@master rc]# kubectl get rc
NAME DESIRED CURRENT READY AGE
nginx 5 5 5 9m
- 启动了多个pod
rc作用：
当node节点上的pod资源在其中一个node挂掉之后，rc会将挂掉的node上的pod资源驱逐到存活的node之上。
示例1：
pod资源删除后，会马上重新创建新的pod。
[root@master rc]# kubectl get pod -o wide
NAME READY STATUS RESTARTS AGE IP NODE
nginx 1/1 Running 0 3d 172.18.42.2 10.0.0.197
nginx-0lrwh 1/1 Running 0 37m 172.18.96.4 10.0.0.163
nginx-7wss6 1/1 Running 0 37m 172.18.42.4 10.0.0.197
nginx-g3pnd 1/1 Running 0 37m 172.18.96.3 10.0.0.163
nginx-j173g 1/1 Running 0 37m 172.18.96.5 10.0.0.163
nginx-pxlbx 1/1 Running 0 37m 172.18.42.5 10.0.0.197
nginxmysql 2/2 Running 0 1h 172.18.42.3 10.0.0.197
test 1/1 Running 0 1h 172.18.96.2 10.0.0.163
[root@master rc]# kubectl delete pod nginx-7wss6
pod "nginx-7wss6" deleted
[root@master rc]# kubectl get pod -o wide
NAME READY STATUS RESTARTS AGE IP NODE
nginx 1/1 Running 0 3d 172.18.42.2 10.0.0.197
nginx-0lrwh 1/1 Running 0 38m 172.18.96.4 10.0.0.163
nginx-g3pnd 1/1 Running 0 38m 172.18.96.3 10.0.0.163
nginx-j173g 1/1 Running 0 38m 172.18.96.5 10.0.0.163
nginx-j7jrw 1/1 Running 0 3s 172.18.42.6 10.0.0.197
nginx-pxlbx 1/1 Running 0 38m 172.18.42.5 10.0.0.197
nginxmysql 2/2 Running 0 1h 172.18.42.3 10.0.0.197
test 1/1 Running 0 1h 172.18.96.2 10.0.0.163
- 示例2：把node2删掉，会出现如下现象
[root@master rc]# kubectl get pod -o wide
NAME READY STATUS RESTARTS AGE IP NODE
nginx 1/1 Running 0 3d 172.18.42.2 10.0.0.197
nginx-0lrwh 1/1 Running 0 3h 172.18.96.4 10.0.0.163
nginx-g3pnd 1/1 Running 0 3h 172.18.96.3 10.0.0.163
nginx-j173g 1/1 Running 0 3h 172.18.96.5 10.0.0.163
nginx-j7jrw 1/1 Running 0 2h 172.18.42.6 10.0.0.197
nginx-pxlbx 1/1 Running 0 3h 172.18.42.5 10.0.0.197
nginxmysql 2/2 Running 1 3h 172.18.42.3 10.0.0.197
test 1/1 Running 0 3h 172.18.96.2 10.0.0.163
[root@master rc]# kubectl delete node 10.0.0.163
node "10.0.0.163" deleted
[root@master rc]# kubectl get pod -o wide
NAME READY STATUS RESTARTS AGE IP NODE
nginx 1/1 Running 0 3d 172.18.42.2 10.0.0.197
nginx-fl07j 1/1 Running 0 2s 172.18.42.7 10.0.0.197
nginx-j7jrw 1/1 Running 0 2h 172.18.42.6 10.0.0.197
nginx-jp6jg 1/1 Running 0 2s 172.18.42.4 10.0.0.197
nginx-pxlbx 1/1 Running 0 3h 172.18.42.5 10.0.0.197
nginx-zr9mw 1/1 Running 0 2s 172.18.42.8 10.0.0.197
nginxmysql 2/2 Running 1 3h 172.18.42.3 10.0.0.197
node2的kubelet重启后会自动注册到集群
rc是通过什么来关联pod的呢？
通过更改[root@master rc]# kubectl edit pod nginx<span> </span>同一标签为myweb后，默认会把pod存活年龄最小的剔除
所以rc的pod资源是有标签选择器来进行维护。
rc滚动升级
- 版本升级：
[root@master rc]# kubectl rolling-update nginx -f k8s_rc1.yaml --update-period=10s
--update-period=10s：升级间隔10s
找一个pod容器进行nginx版本测试
升级成功
- 版本回滚：
[root@master rc]# kubectl rolling-update nginx2 -f k8s_rc.yaml --update-period=1s
版本测试：
- 升级回滚配置文件：
最后总结一下RC（Replica Set）的一些特性与作用。
◎ 在大多数情况下，我们通过定义一个RC实现Pod的创建及副本数量的自动控制。
◎ 在RC里包括完整的Pod定义模板。
◎ RC通过Label Selector机制实现对Pod副本的自动控制。
◎ 通过改变RC里的Pod副本数量，可以实现Pod的扩容或缩容。
◎ 通过改变RC里Pod模板中的镜像版本，可以实现Pod的滚动升级。
2.3 service资源
service帮助pod暴露端口，通过架构图看出通过任何服务可通过kube-proxy组件进行通信。
创建一个service
[root@master svc]# cat k8s_svc.yaml
apiVersion: v1
kind: Service
metadata:
name: myweb
spec:
type: NodePort #ClusterIP
ports:
- port: 80 #clusterIP
nodePort: 30000 #node port
targetPort: 80 #pod port
selector:
app: myweb2
[root@master svc]# kubectl create -f k8s_svc.yaml
注意：
svc标签选择器和rc的标签需要一致，不然访问不了后端服务。
通过：[root@master svc]# kubectl edit svc myweb 修改标签和rc标签一致。
- 再次查看：
- 并且现在和pod的ip相对应
- 查看node服务L:
- 测试服务：
测试负载均衡
- 减少pod节点进行测试
[root@master svc]# kubectl scale rc nginx --replicas=2
调整副本数量的命令
- 进入容器修改index页面
[root@master svc]# kubectl exec -it nginx-175x8 /bin/bash
root@nginx-175x8:/# cd /usr/share/nginx/html/
root@nginx-175x8:/usr/share/nginx/html# ls
50x.html index.html
root@nginx-175x8:/usr/share/nginx/html# echo 'cuijianzhe' > index.html
测试：
- 默认端口范围是30000-32767
修改ports端口数量：
[root@master svc]# vim /etc/kubernetes/apiserver
KUBE_API_ARGS="--service-node-port-range=3000-50000"
[root@master svc]# systemctl restart kube-apiserver
- 添加svc 3000端口
[root@master svc]# cat k8s_svc2.yaml
apiVersion: v1
kind: Service
metadata:
name: myweb2
spec:
type: NodePort #ClusterIP
ports:
- port: 80 #clusterIP
nodePort: 3000 #node port
targetPort: 80 #pod port
selector:
app: myweb2
修改svc统一标签myweb
kubectl edit svc myweb
[root@master svc]# kubectl get svc -o wide
NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR
kubernetes 10.254.0.1 <none> 443/TCP 3d <none>
myweb 10.254.134.169 <nodes> 80:30000/TCP 55m app=myweb
myweb2 10.254.55.214 <nodes> 80:3000/TCP 2m app=myweb
通过一条命令添加service资源
kubectl scale rc nginx --replicas=2
kubectl exec -it pod_name /bin/bash
kubectl expose rc nginx --type=NodePort --port=80
2.4 deployment资源
有rc在滚动升级之后,会造成服务访问中断,于是k8s引入了deployment资源
- 创建deployment
[root@master deploy]# cat k8s_deploy.yaml
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
name: nginx-deployment
spec:
replicas: 3
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: 10.0.0.202:5000/nginx:1.13
ports:
- containerPort: 80
resources:
limits:
cpu: 100m
requests:
cpu: 100m
[root@master deploy]# kubectl create -f k8s_deploy.yaml
deployment "nginx-deployment" created
[root@master deploy]# kubectl get deploy
NAME DESIRED CURRENT UP-TO-DATE AVAILABLE AGE
nginx-deployment 3 3 3 3 18s
给deployment分配端口，出现一个新的svc：
[root@master deploy]# kubectl expose deployment nginx-deployment --type=NodePort --port=80
service "nginx-deployment" exposed
[root@master deploy]# kubectl get svc
NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kubernetes 10.254.0.1 <none> 443/TCP 3d
myweb 10.254.134.169 <nodes> 80:30000/TCP 17h
myweb2 10.254.55.214 <nodes> 80:3000/TCP 16h
nginx-deployment 10.254.2.186 <nodes> 80:33604/TCP 13s
通过curl测试：
滚动升级：
更改[root@master deploy]# kubectl edit deployment nginx-deployment<span> </span>配置文件
[root@master deploy]# kubectl edit deployment nginx-deployment
#将 - image: 10.0.0.202:5000/nginx:1.13 改为
- image: 10.0.0.202:5000/nginx:latest
curl测试升级完成：
升级策略
[root@master deploy]# kubectl edit deployment nginx-deployment
...
strategy:
rollingUpdate:
maxSurge: 1
maxUnavailable: 1
type: RollingUpdate
...
升级回滚
- 第一种
[root@master deploy]# kubectl rollout history deployment nginx-deployment
deployments "nginx-deployment"
REVISION CHANGE-CAUSE
2 <none>
3 <none>
[root@master deploy]# kubectl rollout undo deployment nginx-deployment
deployment "nginx-deployment" rolled back
[root@master deploy]# kubectl rollout history deployment nginx-deployment
deployments "nginx-deployment"
REVISION CHANGE-CAUSE
3 <none>
4 <none>
回滚之后版本：
指定回滚版本号：
[root@master deploy]# kubectl rollout undo deployment nginx-deployment --to-revision=4
deployment "nginx-deployment" rolled back
- 第二种：因为第一种版本号镜像版本没有详细版本，删除deplotment用命令行启动deployment，再次查看会发现具体到相关镜像版本号等信息
[root@master deploy]# kubectl delete deployment nginx-deployment
deployment "nginx-deployment" deleted
[root@master deploy]# kubectl rollout history deployment nginx
deployments "nginx"
REVISION CHANGE-CAUSE
1 kubectl run nginx --image=10.0.0.202:5000/nginx:1.13 --replicas=3 --record
升级版本
[root@master deploy]# kubectl set image deployment nginx nginx=10.0.0.202:5000/nginx:1.16
deployment "nginx" image updated
[root@master deploy]# kubectl rollout history deployment nginx
deployments "nginx"
REVISION CHANGE-CAUSE
1 kubectl run nginx --image=10.0.0.202:5000/nginx:1.13 --replicas=3 --record
2 kubectl edit deployment nginx
3 kubectl set image deployment nginx nginx=10.0.0.202:5000/nginx:1.16
[root@master deploy]# kubectl set image deployment nginx nginx=10.0.0.202:5000/nginx:latest
deployment "nginx" image updated
[root@master deploy]# kubectl rollout history deployment nginx
deployments "nginx"
REVISION CHANGE-CAUSE
1 kubectl run nginx --image=10.0.0.202:5000/nginx:1.13 --replicas=3 --record
3 kubectl set image deployment nginx nginx=10.0.0.202:5000/nginx:1.16
4 kubectl set image deployment nginx nginx=10.0.0.202:5000/nginx:latest
deployment升级和回滚
命令行创建deployment
kubectl run nginx --image=10.0.0.202:5000/nginx:1.13 --replicas=3 --record
命令行升级版本
kubectl set image deploy nginx nginx=10.0.0.202:5000/nginx:1.15
查看deployment所有历史版本
kubectl rollout history deployment nginx
deployment回滚到上一个版本
kubectl rollout undo deployment nginx
deployment回滚到指定版本
kubectl rollout undo deployment nginx --to-revision=2
三、 Tomcat+Mysql练习
在K8S容器之间相互访问,通过VIP地址!
- 启动Mysql yaml配置文件，创建Rc资源
[root@master tomcat_demo]# cat mysql-rc.yaml
apiVersion: v1
kind: ReplicationController
metadata:
name: mysql
spec:
replicas: 1
selector:
app: mysql
template:
metadata:
labels:
app: mysql
spec:
containers:
- name: mysql
image: 10.0.0.202:5000/mysql:5.7
ports:
- containerPort: 3306
env:
- name: MYSQL_ROOT_PASSWORD
value: '598941324'
[root@master tomcat_demo]# kubectl create -f mysql-rc.yaml
replicationcontroller "mysql" created
2.创建Mysql-svc yaml配置文件，创建Service资源
[root@master tomcat_demo]# cat mysql-svc.yaml
apiVersion: v1
kind: Service
metadata:
name: mysql
spec:
# type: NodePort #ClusterIP
ports:
- port: 3306
targetPort: 3306 #pod port
selector:
app: mysql
[root@master tomcat_demo]# kubectl create -f mysql-svc.yaml
service "mysql" created
[root@master tomcat_demo]# kubectl get svc
NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kubernetes 10.254.0.1 <none> 443/TCP 4d
mysql 10.254.76.200 <none> 3306/TCP 1m
myweb 10.254.134.169 <nodes> 80:30000/TCP 1d
myweb2 10.254.55.214 <nodes> 80:3000/TCP 1d
nginx-deployment 10.254.2.186 <nodes> 80:33604/TCP 1d
- Tomcat yaml配置文件，创建Tomcat Rc资源
[root@master tomcat_demo]# cat tomcat-rc.yaml
apiVersion: v1
kind: ReplicationController
metadata:
name: tomcat
spec:
replicas: 1
selector:
app: tomcat
template:
metadata:
labels:
app: tomcat
spec:
containers:
- name: tomcat
image: 10.0.0.202:5000/tomcat:latest
ports:
- containerPort: 8080
env:
- name: MYSQL_SERVICE_HOST
value: '10.254.76.200' #此处是上面查看svc的MySQL CLUSTER-IP
- name: MYSQL_SERVICE_PORT
value: '3306'
- 创建tomcat-svc yaml配置文件，启动tomcat-svc资源
[root@master tomcat_demo]# cat tomcat-svc.yaml
apiVersion: v1
kind: Service
metadata:
name: tomcat
spec:
type: NodePort #ClusterIP
ports:
- port: 8080 #clusterIP
nodePort: 30008 #node port
targetPort: 8080 #pod port
selector:
app: tomcat
[root@master tomcat_demo]# kubectl create -f tomcat-svc.yaml
service "tomcat" created
测试tomcat服务：
