【谷粒商城】集群篇-k8s(4/4)
一、K8s快速入门
1)简介
2)架构
3)概念
4)快速体验
二、K8s集群安装
1)kubeadm
2)前置要求
3)部署步骤
4)环境准备
5)安装所有节点docker、kubeadm、kubelet、kubectl
6)部署k8s-master
7)安装POD网络插件(CNI)
8)加入kubenetes的Node节点
9)入门操作kubernetes集群
三、docker深入
四、K8s细节
1、kubectl文档
2、资源类型
3、格式化输出
命令参考
service的意义
Ingress
安装kubernetes可视化界面——DashBoard
kubesphere
1、简洁
2.安装前提交
版权
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笔记-基础篇-1(P1-P28):https://blog.csdn.net/hancoder/article/details/106922139
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笔记-基础篇-2(P28-P100):https://blog.csdn.net/hancoder/article/details/107612619
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笔记-高级篇(P340):https://blog.csdn.net/hancoder/article/details/107612746
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笔记-vue:https://blog.csdn.net/hancoder/article/details/107007605
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笔记-elastic search、上架、检索:https://blog.csdn.net/hancoder/article/details/113922398
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笔记-认证服务:https://blog.csdn.net/hancoder/article/details/114242184
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笔记-分布式锁和缓存:https://blog.csdn.net/hancoder/article/details/114004280
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笔记-集群篇:https://blog.csdn.net/hancoder/article/details/107612802
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springcloud笔记:https://blog.csdn.net/hancoder/article/details/109063671
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注:2020年提供了注释文件,但只有P1-P2021年整理了50个内容P340内容。点击标题下的栏目查看系列笔记
-
声明:
- 可以白嫖,但请不要转载发布。手打笔记不容易
- 本系列笔记不断迭代优化,csdn:hancoder上面是最新版本的内容,10W字都是在csdn免费开放观看。
- 离线md获取笔记文件的方法见文末。2021-3版md打完笔记,压缩共5000k(云图床)包括项目笔记和cloud、docker、mybatis-plus、rabbitMQ等待个人相关笔记
-
sql:https://github.com/FermHan/gulimall/sql文件
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本项目其他笔记见专栏:https://blog.csdn.net/hancoder/category_10822407.html
一、K8s快速入门
1)简介
kubernetes简称k8s。它是一个开源系统,用于自动部署、扩展和管理容器。 中文官网:https://kubernetes.io/Zh/ 中文社区:https://www.kubernetes.org.cn/ 官方文档:https://kubernetes.io/zh/docs/home/ 社区文档:https://docs.kubernetes.org.cn/
部署模式的演变:
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让我们回顾一下为什么 Kubernetes 如此有用。
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早期,各个组织机构在物理服务器上运行应用程序。无法为物理服务器中的应用程序定义资源边界,这会导致资源分配问题。 例如,如果在物理服务器上运行多个应用程序,则可能会出现一个应用程序占用大部分资源的情况, 结果可能导致其他应用程序的性能下降。 一种解决方案是在不同的物理服务器上运行每个应用程序,但是由于资源利用不足而无法扩展, 并且维护许多物理服务器的成本很高。
作为解决方案,引入了虚拟化。虚拟化技术允许你在单个物理服务器的 CPU 上运行多个虚拟机(VM)。 虚拟化允许应用程序在 VM 之间隔离,并提供一定程度的安全,因为一个应用程序的信息 不能被另一应用程序随意访问。
虚拟化技术能够更好地利用物理服务器上的资源,并且因为可轻松地添加或更新应用程序 而可以实现更好的可伸缩性,降低硬件成本等等。
每个 VM 是一台完整的计算机,在虚拟化硬件之上运行所有组件,包括其自己的操作系统。
容器类似于 VM,但是它们具有被放宽的隔离属性,可以在应用程序之间共享操作系统(OS)。 因此,容器被认为是轻量级的。容器与 VM 类似,具有自己的文件系统、CPU、内存、进程空间等。 由于它们与基础架构分离,因此可以跨云和 OS 发行版本进行移植。
容器因具有许多优势而变得流行起来。下面列出的是容器的一些好处:
- 敏捷应用程序的创建和部署:与使用 VM 镜像相比,提高了容器镜像创建的简便性和效率。
- 持续开发、集成和部署:通过快速简单的回滚(由于镜像不可变性),支持可靠且频繁的 容器镜像构建和部署。
- 关注开发与运维的分离:在构建/发布时而不是在部署时创建应用程序容器镜像, 从而将应用程序与基础架构分离。
- 可观察性不仅可以显示操作系统级别的信息和指标,还可以显示应用程序的运行状况和其他指标信号。
- 跨开发、测试和生产的环境一致性:在便携式计算机上与在云中相同地运行。
- 跨云和操作系统发行版本的可移植性:可在 Ubuntu、RHEL、CoreOS、本地、 Google Kubernetes Engine 和其他任何地方运行。
- 以应用程序为中心的管理:提高抽象级别,从在虚拟硬件上运行 OS 到使用逻辑资源在 OS 上运行应用程序。
- 松散耦合、分布式、弹性、解放的微服务:应用程序被分解成较小的独立部分, 并且可以动态部署和管理 - 而不是在一台大型单机上整体运行。
- 资源隔离:可预测的应用程序性能。
- 资源利用:高效率和高密度。
2)架构
3)概念
4)快速体验
https://github.com/kubernetes/minikube/releases 下载minikuber-windows-amd64.exe 改名为minikube.exe 打开virtualBox,打开cmd 运行 minikube start --vm-driver=virtualbox --registry-mirror=https://registry.docker-cn.com 等待20分钟即可。
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提交一个nginx deployment kubectl apply -f https://k8s.io/examples/application/deployment.yaml
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升级 nginx deployment kubectl apply -f https://k8s.io/examples/application/deployment-update.yaml
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扩容 nginx deployment
二、K8s集群安装
1)kubeadm
kubeadm是官方社区推出的一个用于快速部署kuberneters集群的工具。 这个工具能通过两条指令完成一个kuberneters集群的部署
创建一个master节点
$ kuberneters init
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将一个node节点加入到当前集群中
$ kubeadm join <Master节点的IP和端口>
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2)前置要求
一台或多台机器,操作系统Centos7.x-86_x64 硬件配置:2GB或更多RAM,2个CPU或更多CPU,硬盘30GB或更多 集群中所有的机器之间网络互通 可以访问外网,需要拉取镜像 禁止Swap分区
3)部署步骤
- 在所有的节点上安装Docker和kubeadm
- 不是Kubernetes Master
- 部署容器网络插件
- 部署Kubernetes Node,将节点加入Kubernetes集群中
- 部署DashBoard web页面,可视化查看Kubernetes资源
4)环境准备
- 我们可以使用vagrant快速创建三个虚拟机。虚拟机启动前先设置virtualbox的主机网络。现在全部统一为192.168.56.1,以后所有虚拟机都是56.x的ip地址。
- 在全局设定中,找到一个空间比较大的磁盘用用来存放镜像。
网卡1是NAT,用于虚拟机与本机访问互联网。网卡2是仅主机网络,虚拟机内部共享的虚拟网络
- 使用我们提供的vagrant文件,复制到非中文无空格目录下,运行vagrant up启动三个虚拟机。其实vagrant完全可以一键部署全部K8s集群 https://github.com/rootsongjc/kubernetes-vagrant-centos-cluster http://github.com/davidkbainbridge/k8s-playground
下面是vagrantfile,使用它来创建三个虚拟机,分别为k8s-node1,k8s-node2和k8s-node3.
Vagrant.configure("2") do |config|
(1..3).each do |i|
config.vm.define "k8s-node#{i}" do |node|
# 设置虚拟机的Box
node.vm.box = "centos/7"
# 设置虚拟机的主机名
node.vm.hostname="k8s-node#{i}"
# 设置虚拟机的IP
node.vm.network "private_network", ip: "192.168.56.#{99+i}", netmask: "255.255.255.0"
# 设置主机与虚拟机的共享目录
# node.vm.synced_folder "~/Documents/vagrant/share", "/home/vagrant/share"
# VirtaulBox相关配置
node.vm.provider "virtualbox" do |v|
# 设置虚拟机的名称
v.name = "k8s-node#{i}"
# 设置虚拟机的内存大小
v.memory = 4096
# 设置虚拟机的CPU个数
v.cpus = 4
end
end
end
end
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- 进入到三个虚拟机,开启root的密码访问权限
vagrant ssh xxx进入到系统后
# vagrant ssh k8s-node1
su root 密码为vagrant
vi /etc/ssh/sshd_config
修改
PermitRootLogin yes
PasswordAuthentication yes
所有的虚拟机设为4核4G
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service sshd restart
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192.168.56.100:22
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关于在"网络地址转换"的连接方式下,三个节点的eth0,IP地址相同的问题。
**问题描述:**查看k8s-node1的路由表:
# 查看默认的网卡
[root@k8s-node1 ~]# ip route show
default via 10.0.2.2 dev eth0 proto dhcp metric 100
10.0.2.0/24 dev eth0 proto kernel scope link src 10.0.2.15 metric 100
192.168.56.0/24 dev eth1 proto kernel scope link src 192.168.56.100 metric 101
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能够看到路由表中记录的是,通过端口eth0进行数据包的收发。
分别查看k8s-node1,k8s-node2和k8s-node3的eth0所绑定的IP地址,发现它们都是相同的,全都是10.0.2.15,这些地址是供kubernetes集群通信用的,区别于eth1上的IP地址,是通远程管理使用的。
[root@k8s-node1 ~]# ip addr
...
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
link/ether 52:54:00:8a:fe:e6 brd ff:ff:ff:ff:ff:ff
inet 10.0.2.15/24 brd 10.0.2.255 scope global noprefixroute dynamic eth0
valid_lft 84418sec preferred_lft 84418sec
inet6 fe80::5054:ff:fe8a:fee6/64 scope link
valid_lft forever preferred_lft forever
3: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
link/ether 08:00:27:a3:ca:c0 brd ff:ff:ff:ff:ff:ff
inet 192.168.56.100/24 brd 192.168.56.255 scope global noprefixroute eth1
valid_lft forever preferred_lft forever
inet6 fe80::a00:27ff:fea3:cac0/64 scope link
valid_lft forever preferred_lft forever
[root@k8s-node1 ~]#
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**原因分析:**这是因为它们使用是端口转发规则,使用同一个地址,通过不同的端口来区分。但是这种端口转发规则在以后的使用中会产生很多不必要的问题,所以需要修改为NAT网络类型。
- 选择三个节点,然后执行“管理”->“全局设定”->“网络”,添加一个NAT网络。
- 分别修改每台设备的网络类型,并刷新重新生成MAC地址。
刷新一下MAC地址
1网络是集群交互,2网络是宿主交互
- 再次查看三个节点的IP
- 关闭防火墙
systemctl stop firewalld
systemctl disable firewalld
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- 关闭seLinux
# linux默认的安全策略
sed -i 's/enforcing/disabled/' /etc/selinux/config
setenforce 0
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- 关闭swap
swapoff -a #临时关闭
sed -ri 's/.*swap.*/#&/' /etc/fstab #永久关闭
free -g #验证,swap必须为0
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- 添加主机名与IP对应关系:
查看主机名:
hostname
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如果主机名不正确,可以通过“hostnamectl set-hostname <newhostname> :指定新的hostname”命令来进行修改。
vi /etc/hosts
10.0.2.4 k8s-node1
10.0.2.5 k8s-node2
10.0.2.6 k8s-node3
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将桥接的IPV4流量传递到iptables的链:
cat > /etc/sysctl.d/k8s.conf <<EOF
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
EOF
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应用规则:
sysctl --system
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疑难问题:遇见提示是只读的文件系统,运行如下命令
mount -o remount rw /
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- date 查看时间(可选)
yum -y install ntpupdate
ntpupdate time.window.com #同步最新时间
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5)所有节点安装docker、kubeadm、kubelet、kubectl
Kubenetes默认CRI(容器运行时)为Docker,因此先安装Docker。
1、卸载之前的docker
sudo yum remove docker \
docker-client \
docker-client-latest \
docker-common \
docker-latest \
docker-latest-logrotate \
docker-logrotate \
docker-engine
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2、安装Docker -CE
sudo yum install -y yum-utils \
device-mapper-persistent-data \
lvm2
# 设置docker repo的yum位置
sudo yum-config-manager \
--add-repo \
https://download.docker.com/linux/centos/docker-ce.repo
# 安装docker,docker-cli
sudo yum -y install docker-ce docker-ce-cli containerd.io
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3、配置docker加速
sudo mkdir -p /etc/docker
sudo tee /etc/docker/daemon.json <<-'EOF'
{
"registry-mirrors": ["https://ke9h1pt4.mirror.aliyuncs.com"]
}
EOF
sudo systemctl daemon-reload
sudo systemctl restart docker
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4、启动Docker && 设置docker开机启动
systemctl enable docker
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基础环境准备好,可以给三个虚拟机备份一下;
cat <<EOF > /etc/yum.repos.d/kubernetes.repo
[kubernetes]
name=Kubernetes
baseurl=https://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64/
enabled=1
gpgcheck=1
repo_gpgcheck=1
gpgkey=https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg https://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
EOF
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更多详情见: https://developer.aliyun.com/mirror/kubernetes
yum list|grep kube
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安装
yum install -y kubelet-1.17.3 kubeadm-1.17.3 kubectl-1.17.3
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开机启动
systemctl enable kubelet && systemctl start kubelet
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查看kubelet的状态:
systemctl status kubelet
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查看kubelet版本:
[root@k8s-node2 ~]# kubelet --version
Kubernetes v1.17.3
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6)部署k8s-master
在Master节点上,创建并执行master_images.sh
#!/bin/bash
images=(
kube-apiserver:v1.17.3
kube-proxy:v1.17.3
kube-controller-manager:v1.17.3
kube-scheduler:v1.17.3
coredns:1.6.5
etcd:3.4.3-0
pause:3.1
)
for imageName in ${images[@]} ; do
docker pull registry.cn-hangzhou.aliyuncs.com/google_containers/$imageName
# docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/$imageName k8s.gcr.io/$imageName
done
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查看100的内部通信端口
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
link/ether 08:00:27:7e:dd:f5 brd ff:ff:ff:ff:ff:ff
inet 10.0.2.4/24 brd 10.0.2.255 scope global noprefixroute dynamic eth0
valid_lft 512sec preferred_lft 512sec
inet6 fe80::a00:27ff:fe7e:ddf5/64 scope link
valid_lft forever preferred_lft forever
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初始化kubeadm
kubeadm init \
--apiserver-advertise-address=10.0.2.4 \
--image-repository registry.cn-hangzhou.aliyuncs.com/google_containers \
--kubernetes-version v1.17.3 \
--service-cidr=10.96.0.0/16 \
--pod-network-cidr=10.244.0.0/16
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注:
- –apiserver-advertise-address=10.0.2.21 :这里的IP地址是master主机的地址,为上面的eth0网卡的地址;
执行结果:
[root@k8s-node1 opt]# kubeadm init \
> --apiserver-advertise-address=10.0.2.15 \
> --image-repository registry.cn-hangzhou.aliyuncs.com/google_containers \
> --kubernetes-version v1.17.3 \
> --service-cidr=10.96.0.0/16 \
> --pod-network-cidr=10.244.0.0/16
W0503 14:07:12.594252 10124 configset.go:202] WARNING: kubeadm cannot validate component configs for API groups [kubelet.config.k8s.io kubeproxy.config.k8s.io]
[init] Using Kubernetes version: v1.17.3
[preflight] Running pre-flight checks
[WARNING IsDockerSystemdCheck]: detected "cgroupfs" as the Docker cgroup driver. The recommended driver is "systemd". Please follow the guide at https://kubernetes.io/docs/setup/cri/
[preflight] Pulling images required for setting up a Kubernetes cluster
[preflight] This might take a minute or two, depending on the speed of your internet connection
[preflight] You can also perform this action in beforehand using 'kubeadm config images pull'
[kubelet-start] Writing kubelet environment file with flags to file "/var/lib/kubelet/kubeadm-flags.env"
[kubelet-start] Writing kubelet configuration to file "/var/lib/kubelet/config.yaml"
[kubelet-start] Starting the kubelet
[certs] Using certificateDir folder "/etc/kubernetes/pki"
[certs] Generating "ca" certificate and key
[certs] Generating "apiserver" certificate and key
[certs] apiserver serving cert is signed for DNS names [k8s-node1 kubernetes kubernetes.default kubernetes.default.svc kubernetes.default.svc.cluster.local] and IPs [10.96.0.1 10.0.2.15]
[certs] Generating "apiserver-kubelet-client" certificate and key
[certs] Generating "front-proxy-ca" certificate and key
[certs] Generating "front-proxy-client" certificate and key
[certs] Generating "etcd/ca" certificate and key
[certs] Generating "etcd/server" certificate and key
[certs] etcd/server serving cert is signed for DNS names [k8s-node1 localhost] and IPs [10.0.2.15 127.0.0.1 ::1]
[certs] Generating "etcd/peer" certificate and key
[certs] etcd/peer serving cert is signed for DNS names [k8s-node1 localhost] and IPs [10.0.2.15 127.0.0.1 ::1]
[certs] Generating "etcd/healthcheck-client" certificate and key
[certs] Generating "apiserver-etcd-client" certificate and key
[certs] Generating "sa" key and public key
[kubeconfig] Using kubeconfig folder "/etc/kubernetes"
[kubeconfig] Writing "admin.conf" kubeconfig file
[kubeconfig] Writing "kubelet.conf" kubeconfig file
[kubeconfig] Writing "controller-manager.conf" kubeconfig file
[kubeconfig] Writing "scheduler.conf" kubeconfig file
[control-plane] Using manifest folder "/etc/kubernetes/manifests"
[control-plane] Creating static Pod manifest for "kube-apiserver"
[control-plane] Creating static Pod manifest for "kube-controller-manager"
W0503 14:07:30.908642 10124 manifests.go:225] the default kube-apiserver authorization-mode is "Node,RBAC"; using "Node,RBAC"
[control-plane] Creating static Pod manifest for "kube-scheduler"
W0503 14:07:30.911330 10124 manifests.go:225] the default kube-apiserver authorization-mode is "Node,RBAC"; using "Node,RBAC"
[etcd] Creating static Pod manifest for local etcd in "/etc/kubernetes/manifests"
[wait-control-plane] Waiting for the kubelet to boot up the control plane as static Pods from directory "/etc/kubernetes/manifests". This can take up to 4m0s
[apiclient] All control plane components are healthy after 22.506521 seconds
[upload-config] Storing the configuration used in ConfigMap "kubeadm-config" in the "kube-system" Namespace
[kubelet] Creating a ConfigMap "kubelet-config-1.18" in namespace kube-system with the configuration for the kubelets in the cluster
[upload-certs] Skipping phase. Please see --upload-certs
[mark-control-plane] Marking the node k8s-node1 as control-plane by adding the label "node-role.kubernetes.io/master=''"
[mark-control-plane] Marking the node k8s-node1 as control-plane by adding the taints [node-role.kubernetes.io/master:NoSchedule]
[bootstrap-token] Using token: sg47f3.4asffoi6ijb8ljhq
[bootstrap-token] Configuring bootstrap tokens, cluster-info ConfigMap, RBAC Roles
[bootstrap-token] configured RBAC rules to allow Node Bootstrap tokens to get nodes
[bootstrap-token] configured RBAC rules to allow Node Bootstrap tokens to post CSRs in order for nodes to get long term certificate credentials
[bootstrap-token] configured RBAC rules to allow the csrapprover controller automatically approve CSRs from a Node Bootstrap Token
[bootstrap-token] configured RBAC rules to allow certificate rotation for all node client certificates in the cluster
[bootstrap-token] Creating the "cluster-info" ConfigMap in the "kube-public" namespace
[kubelet-finalize] Updating "/etc/kubernetes/kubelet.conf" to point to a rotatable kubelet client certificate and key
[addons] Applied essential addon: CoreDNS
[addons] Applied essential addon: kube-proxy
#表示kubernetes已经初始化成功了
Your Kubernetes control-plane has initialized successfully!
To start using your cluster, you need to run the following as a regular user:
mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config
You should now deploy a pod network to the cluster.
Run "kubectl apply -f [podnetwork].yaml" with one of the options listed at:
https://kubernetes.io/docs/concepts/cluster-administration/addons/
Then you can join any number of worker nodes by running the following on each as root:
kubeadm join 10.0.2.15:6443 --token sg47f3.4asffoi6ijb8ljhq \
--discovery-token-ca-cert-hash sha256:81fccdd29970cbc1b7dc7f171ac0234d53825bdf9b05428fc9e6767436991bfb
[root@k8s-node1 opt]#
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由于默认拉取镜像地址k8s.cr.io国内无法访问,这里指定阿里云仓库地址。可以手动按照我们的images.sh先拉取镜像。
地址变为:registry.aliyuncs.com/googole_containers也可以。 科普:无类别域间路由(Classless Inter-Domain Routing 、CIDR)是一个用于给用户分配IP地址以及在互联网上有效第路由IP数据包的对IP地址进行归类的方法。 拉取可能失败,需要下载镜像。
运行完成提前复制:加入集群的令牌。
mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config
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详细部署文档:https://kubernetes.io/docs/concepts/cluster-administration/addons/
kubectl get nodes #获取所有节点
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目前Master状态为notready。等待网络加入完成即可。
journalctl -u kubelet #查看kubelet日志
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kubeadm join 10.0.2.4:6443 --token bt3hkp.yxnpzsgji4a6edy7 \
--discovery-token-ca-cert-hash sha256:64949994a89c53e627d68b115125ff753bfe6ff72a26eb561bdc30f32837415a
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7)安装POD网络插件(CNI)
在master节点上执行按照POD网络插件
kubectl apply -f \
https://raw.githubusercontent.com/coreos/flanne/master/Documentation/kube-flannel.yml
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以上地址可能被墙,可以直接获取本地已经下载的flannel.yml运行即可(https://blog.csdn.net/lxm1720161656/article/details/106436252 可以去下载),如:
[root@k8s-node1 k8s]# kubectl apply -f kube-flannel.yml
podsecuritypolicy.policy/psp.flannel.unprivileged created
clusterrole.rbac.authorization.k8s.io/flannel created
clusterrolebinding.rbac.authorization.k8s.io/flannel created
serviceaccount/flannel created
configmap/kube-flannel-cfg created
daemonset.apps/kube-flannel-ds-amd64 created
daemonset.apps/kube-flannel-ds-arm64 created
daemonset.apps/kube-flannel-ds-arm created
daemonset.apps/kube-flannel-ds-ppc64le created
daemonset.apps/kube-flannel-ds-s390x created
[root@k8s-node1 k8s]#
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同时flannel.yml中指定的images访问不到可以去docker hub找一个wget yml地址 vi 修改yml 所有amd64的地址修改了即可 等待大约3分钟 kubectl get pods -n kube-system 查看指定名称空间的pods kubectl get pods -all-namespace 查看所有名称空间的pods
$ ip link set cni0 down 如果网络出现问题,关闭cni0,重启虚拟机继续测试 执行watch kubectl get pod -n kube-system -o wide 监控pod进度 等待3-10分钟,完全都是running以后继续
查看命名空间:
[root@k8s-node1 k8s]# kubectl get ns
NAME STATUS AGE
default Active 30m
kube-node-lease Active 30m
kube-public Active 30m
kube-system Active 30m
[root@k8s-node1 k8s]#
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[root@k8s-node1 k8s]# kubectl get pods --all-namespaces
NAMESPACE NAME READY STATUS RESTARTS AGE
kube-system coredns-546565776c-9sbmk 0/1 Pending 0 31m
kube-system coredns-546565776c-t68mr 0/1 Pending 0 31m
kube-system etcd-k8s-node1 1/1 Running 0 31m
kube-system kube-apiserver-k8s-node1 1/1 Running 0 31m
kube-system kube-controller-manager-k8s-node1 1/1 Running 0 31m
kube-system kube-flannel-ds-amd64-6xwth 1/1 Running 0 2m50s
kube-system kube-proxy-sz2vz 1/1 Running 0 31m
kube-system kube-scheduler-k8s-node1 1/1 Running 0 31m
[root@k8s-node1 k8s]#
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查看master上的节点信息:
[root@k8s-node1 k8s]# kubectl get nodes
NAME STATUS ROLES AGE VERSION
k8s-node1 Ready master 34m v1.17.3 #status为ready才能够执行下面的命令
[root@k8s-node1 k8s]#
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最后再次执行,并且分别在“k8s-node2
”和“k8s-node3
”上也执行这里命令:
kubeadm join 10.0.2.4:6443 --token bt3hkp.yxnpzsgji4a6edy7 \
--discovery-token-ca-cert-hash sha256:64949994a89c53e627d68b115125ff753bfe6ff72a26eb561bdc30f32837415a
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[root@k8s-node1 opt]# kubectl get nodes;
NAME STATUS ROLES AGE VERSION
k8s-node1 Ready master 47m v1.17.3
k8s-node2 NotReady <none> 75s v1.17.3
k8s-node3 NotReady <none> 76s v1.17.3
[root@k8s-node1 opt]#
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监控pod进度
# 在master执行
watch kubectl get pod -n kube-system -o wide
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等到所有的status都变为running状态后,再次查看节点信息:
[root@k8s-node1 ~]# kubectl get nodes;
NAME STATUS ROLES AGE VERSION
k8s-node1 Ready master 3h50m v1.17.3
k8s-node2 Ready <none> 3h3m v1.17.3
k8s-node3 Ready <none> 3h3m v1.17.3
[root@k8s-node1 ~]#
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8)加入kubenetes的Node节点
在node节点中执行,向集群中添加新的节点,执行在kubeadm init 输出的kubeadm join命令; 确保node节点成功: token过期怎么办 kubeadm token create --print-join-command
9)入门操作kubernetes集群
kubectl create deployment tomcat6 --image=tomcat:6.0.53-jre8
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获取所有的资源:
[root@k8s-node1 k8s]# kubectl get all
NAME READY STATUS RESTARTS AGE
pod/tomcat6-7b84fb5fdc-cfd8g 0/1 ContainerCreating 0 41s
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 70m
NAME READY UP-TO-DATE AVAILABLE AGE
deployment.apps/tomcat6 0/1 1 0 41s
NAME DESIRED CURRENT READY AGE
replicaset.apps/tomcat6-7b84fb5fdc 1 1 0 41s
[root@k8s-node1 k8s]#
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kubectl get pods -o wide 可以获取到tomcat部署信息,能够看到它被部署到了k8s-node3上了
[root@k8s-node1 k8s]# kubectl get all -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
pod/tomcat6-5f7ccf4cb9-xhrr9 0/1 ContainerCreating 0 77s <none> k8s-node3 <none> <none>
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR
service/kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 68m <none>
NAME READY UP-TO-DATE AVAILABLE AGE CONTAINERS IMAGES SELECTOR
deployment.apps/tomcat6 0/1 1 0 77s tomcat tomcat:6.0.53-jre8 app=tomcat6
NAME DESIRED CURRENT READY AGE CONTAINERS IMAGES SELECTOR
replicaset.apps/tomcat6-5f7ccf4cb9 1 1 0 77s tomcat tomcat:6.0.53-jre8 app=tomcat6,pod-template-hash=5f7ccf4cb9
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查看node3节点上,下载了哪些镜像:
[root@k8s-node3 k8s]# docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
registry.cn-hangzhou.aliyuncs.com/google_containers/kube-proxy v1.17.3 ae853e93800d 14 months ago 116MB
quay.io/coreos/flannel v0.11.0-amd64 ff281650a721 2 years ago 52.6MB
registry.cn-hangzhou.aliyuncs.com/google_containers/pause 3.1 da86e6ba6ca1 3 years ago 742kB
tomcat 6.0.53-jre8 49ab0583115a 3 years ago 290MB
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查看Node3节点上,正在运行的容器:
[root@k8s-node3 k8s]# docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
8a197fa41dd9 tomcat "catalina.sh run" About a minute ago Up About a minute k8s_tomcat_tomcat6-5f7ccf4cb9-xhrr9_default_81f186a8-4805-4bbb-8d77-3142269942ed_0
4074d0d63a88 registry.cn-hangzhou.aliyuncs.com/google_containers/pause:3.1 "/pause" 2 minutes ago Up 2 minutes k8s_POD_tomcat6-5f7ccf4cb9-xhrr9_default_81f186a8-4805-4bbb-8d77-3142269942ed_0
db3faf3a280d ff281650a721 "/opt/bin/flanneld -…" 29 minutes ago Up 29 minutes k8s_kube-flannel_kube-flannel-ds-amd64-vcktd_kube-system_31ca3556-d6c3-48b2-b393-35ff7d89a078_0
be461b54cb4b registry.cn-hangzhou.aliyuncs.com/google_containers/kube-proxy "/usr/local/bin/kube…" 30 minutes ago Up 30 minutes k8s_kube-proxy_kube-proxy-ptq2t_kube-system_0e1f7df3-7204-481d-bf15-4b0e09cf0c81_0
88d1ab87f400 registry.cn-hangzhou.aliyuncs.com/google_containers/pause:3.1 "/pause" 31 minutes ago Up 31 minutes k8s_POD_kube-flannel-ds-amd64-vcktd_kube-system_31ca3556-d6c3-48b2-b393-35ff7d89a078_0
52be28610a02 registry.cn-hangzhou.aliyuncs.com/google_containers/pause:3.1 "/pause" 31 minutes ago Up 31 minutes k8s_POD_kube-proxy-ptq2t_kube-system_0e1f7df3-7204-481d-bf15-4b0e09cf0c81_0
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在node1上执行:
[root@k8s-node1 k8s]# kubectl get pods
NAME READY STATUS RESTARTS AGE
tomcat6-7b84fb5fdc-cfd8g 1/1 Running 0 5m35s
[root@k8s-node1 k8s]# kubectl get pods --all-namespaces
NAMESPACE NAME READY STATUS RESTARTS AGE
default tomcat6-7b84fb5fdc-cfd8g 1/1 Running 0 163m
kube-system coredns-546565776c-9sbmk 1/1 Running 0 3h52m
kube-system coredns-546565776c-t68mr 1/1 Running 0 3h52m
kube-system etcd-k8s-node1 1/1 Running 0 3h52m
kube-system kube-apiserver-k8s-node1 1/1 Running 0 3h52m
kube-system kube-controller-manager-k8s-node1 1/1 Running 0 3h52m
kube-system kube-flannel-ds-amd64-5xs5j 1/1 Running 0 3h6m
kube-system kube-flannel-ds-amd64-6xwth 1/1 Running 0 3h24m
kube-system kube-flannel-ds-amd64-fvnvx 1/1 Running 0 3h6m
kube-system kube-proxy-7tkvl 1/1 Running 0 3h6m
kube-system kube-proxy-mvlnk 1/1 Running 0 3h6m
kube-system kube-proxy-sz2vz 1/1 Running 0 3h52m
kube-system kube-scheduler-k8s-node1 1/1 Running 0 3h52m
[root@k8s-node1 ~]#
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从前面看到tomcat部署在Node3上,现在模拟因为各种原因宕机的情况,将node3关闭电源,观察情况。
docker stop执行的时候,docker ps发现又有新的容器了,这是k8s又新建了,所以选择关机node3
[root@k8s-node1 k8s]# kubectl get nodes
NAME STATUS ROLES AGE VERSION
k8s-node1 Ready master 79m v1.17.3
k8s-node2 Ready <none> 41m v1.17.3
k8s-node3 NotReady <none> 41m v1.17.3
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得等个几分钟才能容灾恢复
[root@k8s-node1 k8s]# kubectl get pods -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
tomcat6-5f7ccf4cb9-clcpr 1/1 Running 0 4m16s 10.244.1.2 k8s-node2 <none> <none>
tomcat6-5f7ccf4cb9-xhrr9 1/1 Terminating 1 22m 10.244.2.2 k8s-node3 <none> <none>
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在master上执行
kubectl expose deployment tomcat6 --port=80 --target-port=8080 --type=NodePort
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pod的80映射容器的8080;server会带来pod的80
查看服务:
[root@k8s-node1 k8s]# kubectl get svc
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 93m
tomcat6 NodePort 10.96.7.78 <none> 80:30055/TCP 8s
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[root@k8s-node1 k8s]# kubectl get svc -o wide
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR
kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 103m <none>
tomcat6 NodePort 10.96.7.78 <none> 80:30055/TCP 9m38s app=tomcat6
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浏览器输入:http://192.168.56.100:30055/ ,可以看到tomcat首页
输入下面命令可以看到pod和封装pod 的service,pod是部署产生的,部署还有一个副本
[root@k8s-node1 ~]# kubectl get all
NAME READY STATUS RESTARTS AGE
pod/tomcat6-5f7ccf4cb9-clcpr 1/1 Running 0 4h12m
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 5h37m
service/tomcat6 NodePort 10.96.7.78 <none> 80:30055/TCP 4h3m
NAME READY UP-TO-DATE AVAILABLE AGE
deployment.apps/tomcat6 1/1 1 1 4h30m
NAME DESIRED CURRENT READY AGE
replicaset.apps/tomcat6-5f7ccf4cb9 1 1 1 4h30m
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kubectl get deployment
[root@k8s-node1 ~]# kubectl get deployment
NAME READY UP-TO-DATE AVAILABLE AGE
tomcat6 2/2 2 2 11h
[root@k8s-node1 ~]#
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应用升级: kubectl set image (–help查看帮助) 扩容:kubectl scale --replicas=3 deployment tomcat6
[root@k8s-node1 ~]# kubectl scale --replicas=3 deployment tomcat6
deployment.apps/tomcat6 scaled
[root@k8s-node1 ~]# kubectl get pods -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
tomcat6-5f7ccf4cb9-clcpr 1/1 Running 0 4h23m 10.244.1.2 k8s-node2 <none> <none>
tomcat6-5f7ccf4cb9-jbvr4 1/1 Running 0 9s 10.244.2.3 k8s-node3 <none> <none>
tomcat6-5f7ccf4cb9-ng556 1/1 Running 0 9s 10.244.2.4 k8s-node3 <none> <none>
[root@k8s-node1 ~]# kubectl get svc -o wide
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR
kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 5h48m <none>
tomcat6 NodePort 10.96.7.78 <none> 80:30055/TCP 4h15m app=tomcat6
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扩容了多份,所有无论访问哪个node的指定端口,都可以访问到tomcat6
http://192.168.56.101:30055/
http://192.168.56.102:30055/
缩容:kubectl scale --replicas=2 deployment tomcat6
[root@k8s-node1 ~]# kubectl scale --replicas=1 deployment tomcat6
deployment.apps/tomcat6 scaled
[root@k8s-node1 ~]# kubectl get pods -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
tomcat6-5f7ccf4cb9-clcpr 1/1 Running 0 4h32m 10.244.1.2 k8s-node2 <none> <none>
[root@k8s-node1 ~]# kubectl get all
NAME READY STATUS RESTARTS AGE
pod/tomcat6-5f7ccf4cb9-clcpr 1/1 Running 0 4h33m
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 5h58m
service/tomcat6 NodePort 10.96.7.78 <none> 80:30055/TCP 4h24m
NAME READY UP-TO-DATE AVAILABLE AGE
deployment.apps/tomcat6 1/1 1 1 4h51m
NAME DESIRED CURRENT READY AGE
replicaset.apps/tomcat6-5f7ccf4cb9 1 1 1 4h51m
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4、以上操作的yaml获取 参照k8s细节
5、删除 kubectl get all
[root@k8s-node1 ~]# kubectl get all
NAME READY STATUS RESTARTS AGE
pod/tomcat6-5f7ccf4cb9-clcpr 1/1 Running 0 4h33m
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 5h58m
service/tomcat6 NodePort 10.96.7.78 <none> 80:30055/TCP 4h24m
NAME READY UP-TO-DATE AVAILABLE AGE
deployment.apps/tomcat6 1/1 1 1 4h51m
NAME DESIRED CURRENT READY AGE
replicaset.apps/tomcat6-5f7ccf4cb9 1 1 1 4h51m
#删除deployment.apps/tomcat6
[root@k8s-node1 ~]# kubectl delete deployment.apps/tomcat6
deployment.apps "tomcat6" deleted
#查看剩余的资源
[root@k8s-node1 ~]# kubectl get all
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 6h
service/tomcat6 NodePort 10.96.7.78 <none> 80:30055/TCP 4h26m
# 此时没有了部署,但是有service,没有pod只有service也是没有对应的服务的
# 查看pod信息
[root@k8s-node1 ~]# kubectl get pods
No resources found in default namespace.
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kubectl delete deploye/nginx kubectl delete service/nginx-service
三、docker深入
四、K8s细节
1、kubectl文档
https://kubernetes.io/zh/docs/reference/kubectl/overview/
2、资源类型
https://kubernetes.io/zh/docs/reference/kubectl/overview/#资源类型
3、格式化输出
https://kubernetes.io/zh/docs/reference/kubectl/overview/
所有
kubectl
命令的默认输出格式都是人类可读的纯文本格式。要以特定格式向终端窗口输出详细信息,可以将-o
或--output
参数添加到受支持的kubectl
命令中。kubectl [command] [TYPE] [NAME] -o=<output_format>
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根据
kubectl
操作,支持以下输出格式:
Output format Description -o custom-columns=
使用逗号分隔的自定义列列表打印表。 -o custom-columns-file=
使用 `` 文件中的自定义列模板打印表。 -o json
输出 JSON 格式的 API 对象 `-o jsonpath= 打印 jsonpath 表达式定义的字段 -o jsonpath-file=
打印 `` 文件中 jsonpath 表达式定义的字段。 -o name
仅打印资源名称而不打印任何其他内容。 -o wide
以纯文本格式输出,包含任何附加信息。对于 pod 包含节点名。 -o yaml
输出 YAML 格式的 API 对象。 在此示例中,以下命令将单个 pod 的详细信息输出为 YAML 格式的对象:
kubectl get pod web-pod-13je7 -o yaml
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请记住:有关每个命令支持哪种输出格式的详细信息,请参阅 kubectl 参考文档。
–dry-run:
–dry-run=‘none’: Must be “none”, “server”, or “client”. If client strategy, only print the object that would be
sent, without sending it. If server strategy, submit server-side request without persisting the resource.
值必须为none,server或client。如果是客户端策略,则只打印该发送对象,但不发送它。如果服务器策略,提交服务器端请求而不持久化资源。
也就是说,通过–dry-run选项,并不会真正的执行这条命令。
[root@k8s-node1 ~]# kubectl create deployment tomcat6 --image=tomcat:6.0.53-jre8 --dry-run -o yaml
W0504 03:39:08.389369 8107 helpers.go:535] --dry-run is deprecated and can be replaced with --dry-run=client.
apiVersion: apps/v1
kind: Deployment
metadata:
creationTimestamp: null
labels:
app: tomcat6
name: tomcat6
spec:
replicas: 1
selector:
matchLabels:
app: tomcat6
strategy: {}
template:
metadata:
creationTimestamp: null
labels:
app: tomcat6
spec:
containers:
- image: tomcat:6.0.53-jre8
name: tomcat
resources: {}
status: {}
[root@k8s-node1 ~]#
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实际上我们也可以将这个yaml输出到文件,然后使用kubectl apply -f来应用它
#输出到tomcat6.yaml
[root@k8s-node1 ~]# kubectl create deployment tomcat6 --image=tomcat:6.0.53-jre8 --dry-run -o yaml >tomcat6.yaml
W0504 03:46:18.180366 11151 helpers.go:535] --dry-run is deprecated and can be replaced with --dry-run=client.
#修改副本数为3
[root@k8s-node1 ~]# cat tomcat6.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
creationTimestamp: null
labels:
app: tomcat6
name: tomcat6
spec:
replicas: 3 #修改副本数为3
selector:
matchLabels:
app: tomcat6
strategy: {}
template:
metadata:
creationTimestamp: null
labels:
app: tomcat6
spec:
containers:
- image: tomcat:6.0.53-jre8
name: tomcat
resources: {}
status: {}
#应用tomcat6.yaml
[root@k8s-node1 ~]# kubectl apply -f tomcat6.yaml
deployment.apps/tomcat6 created
[root@k8s-node1 ~]#
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查看pods:
[root@k8s-node1 ~]# kubectl get pods
NAME READY STATUS RESTARTS AGE
tomcat6-7b84fb5fdc-5jh6t 1/1 Running 0 8s
tomcat6-7b84fb5fdc-8lhwv 1/1 Running 0 8s
tomcat6-7b84fb5fdc-j