kubeadm部署 Kubernetes(k8s) 高可用集群【V1.20 】

kubeadm是官方社区推出的一个用于快速部署kubernetes集群的工具。
calico.yaml
kubernertes-dashboard.yaml

1. 安装要求

在开始之前，部署Kubernetes集群机器需要满足以下几个条件：

7台机器，操作系统Openeuler22.03 LTS SP4
硬件配置：2GB或更多RAM，2个CPU或更多CPU，硬盘30GB或更多，docker 数据卷单独挂载
集群中所有机器之间网络互通
可以访问外网，需要拉取镜像，【镜像代理自行解决】
禁止swap分区

2. 准备环境

角色	IP	组件	功能描述
Haproxy	172.22.33.210	Haproxy	haproxy 负载均衡
k8s-master01	172.22.33.215	docker，cri-dockerd，kube-apiserver，kube-scheduler，kube-controller-manager，etcd，kubelet，kube-proxy，coredns，calico	k8s master01节点，etcd01节点
k8s-master02	172.22.33.216	docker，cri-dockerd，kube-apiserver，kube-scheduler，kube-controller-manager，etcd，kubelet，kube-proxy，calico	k8s master02节点，etcd02节点
k8s-master03	172.22.33.217	docker，cri-dockerd，kube-apiserver，kube-scheduler，kube-controller-manager，etcd，kubelet，kube-proxy，calico	k8s master03节点，etcd03节点
k8s-node01	172.22.33.218	docker，cri-dockerd，kubelet，kube-proxy，coredns，calico	k8s-node01 工作节点
k8s-node02	172.22.33.219	docker，cri-dockerd，kubelet，kube-proxy，coredns，calico	k8s-node02 工作节点
k8s-node03	172.22.33.220	docker，cri-dockerd，kubelet，kube-proxy，coredns，calico	k8s-node03工作节点

2.1 环境初始化

K8S 集群服务器都需要配置

关闭防火墙：
$ systemctl stop firewalld
$ systemctl disable firewalld

关闭selinux：
$ sed -i 's/enforcing/disabled/' /etc/selinux/config  # 永久
$ setenforce 0  # 临时

关闭swap：[临时和永久关闭]
#临时关闭
$ swapoff -a

#永久关闭
$ sed -ri 's/.*swap.*/#&/' /etc/fstab


设置主机名：
$ hostnamectl set-hostname k8s-master01
$ hostnamectl set-hostname k8s-master02
$ hostnamectl set-hostname k8s-master03
$ hostnamectl set-hostname k8s-node01
$ hostnamectl set-hostname k8s-node02
$ hostnamectl set-hostname k8s-node03


#在K8S上所有节点添加hosts：
$ cat >> /etc/hosts << EOF
172.22.33.215 k8s-master01
172.22.33.216 k8s-master02
172.22.33.217 k8s-master03
172.22.33.218 k8s-node01
172.22.33.219 k8s-node02
172.22.33.220 k8s-node03
EOF


#开启内核路由转发
sed -i 's/net.ipv4.ip_forward=0/net.ipv4.ip_forward=1/g' /etc/sysctl.conf


#将桥接的IPv4,IPV6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
vm.swappiness = 0
EOF

# 生效
$ sysctl --system


#每个节点都需要安装 IPVS 的相关工具和加载ipvs内核模块
$ yum install ipvsadm

#在所有节点执行以下命令
$ cat > /etc/sysconfig/modules/ipvs.modules <<EOF
#!/bin/bash
modprobe -- ip_vs
modprobe -- ip_vs_rr
modprobe -- ip_vs_wrr
modprobe -- ip_vs_sh
modprobe -- nf_conntrack_ipv4
EOF

$ chmod 755 /etc/sysconfig/modules/ipvs.modules
$ bash /etc/sysconfig/modules/ipvs.modules

#查看IPVS模块加载情况
$ lsmod | grep -e ip_vs -e nf_conntrack_ipv4
#能看到ip_vs ip_vs_rr ip_vs_wrr  ip_vs_sh nf_conntrack_ipv4  加载成功


时间同步：
$ yum install ntpdate -y
$ ntpdate ntp.ntsc.ac.cn

3. 安装Docker/kubeadm/kubelet/kubectl

在所有K8S 集群的节点上，执行

3.1.1 docker二进制包下载

docker-ce 社区下载地址：

$ wget https://mirrors.nju.edu.cn/docker-ce/linux/static/stable/x86_64/docker-20.10.24.tgz

3.1.2 解压，拷贝至/usr/bin 下

$ tar -xf docker-20.10.24.tgz
$ cp docker/* /usr/bin
$ which docker

3.1.3 编写docker.service文件

$ cat > /etc/systemd/system/docker.service <<EOF

[Unit]
Description=Docker Application Container Engine
Documentation=https://docs.docker.com
After=network-online.target firewalld.service
Wants=network-online.target

[Service]
Type=notify
ExecStart=/usr/bin/dockerd
ExecReload=/bin/kill -s HUP $MAINPID
LimitNOFILE=65535
LimitNPROC=65535
LimitCORE=65535
TimeoutStartSec=0
Delegate=yes
KillMode=process
Restart=on-failure
StartLimitBurst=3
StartLimitInterval=60s

[Install]
WantedBy=multi-user.target

EOF

3.1.4 挂载docker默认存储路径[可选]

docker的默认工作路径在/var/lib/docker ，最好不修改默认存储路径，可以做软链接

#建立工作目录
$ mkdir /home/application/

#格式化磁盘
$ mkfs.ext4 /dev/sdb

#磁盘永久挂载
$ vim /etc/fstab
/dev/sdb  /home/application  ext4 defaults 0 0

#使挂载生效
$ mount -a


# 创建docker 工作目录
$ mkdir /home/application/docker


#创建软链接
$ ln -s /home/application/docker /var/lib/

3.1.5 添加可执行权限

$ chmod +x /etc/systemd/system/docker.service

3.1.6 启动，加载，开机自启动

$ systemctl daemon-reload
$ systemctl start docker.service
$ systemctl enable docker.service

3.1.7 配置镜像加速器

$ mkdir -p /etc/docker
$ tee /etc/docker/daemon.json <<-'EOF'
{
  "registry-mirrors": ["https://docker.srebro.cn"],
  "exec-opts": ["native.cgroupdriver=systemd"]
}
EOF

$ systemctl daemon-reload
$ systemctl restart docker

⚠️tips：
如果仓库不是https 的，需要在 /etc/docker/daemon.json 中添加忽略；比如下方的示例

"insecure-registries": [
    "https://harbor.srebro.cn",
    "https://it-docker.pkg.devops.com"
  ]

3.2.1 添加阿里云YUM软件源

$ cat > /etc/yum.repos.d/kubernetes.repo << EOF
[kubernetes]
name=Kubernetes
baseurl=https://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64
enabled=1
gpgcheck=0
repo_gpgcheck=0
gpgkey=https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg https://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
EOF

3.2.2 安装kubeadm，kubelet和kubectl

由于版本更新频繁，这里指定版本号部署：

# 查看所有的可用版本
$ yum list  kubeadm  kubelet kubectl --showduplicates | sort -r


#在所有节点安装
$ yum install -y kubelet-1.20.15 kubeadm-1.20.15 kubectl-1.20.15

$ systemctl enable kubelet

4. 部署Haproxy负载均衡

4.1 yum安装haproxy

在172.22.33.210 服务器上部署

yum  -y install haproxy

4.2 修改配置文件

$ cat > /etc/haproxy/haproxy.cfg << EOF
global
    log /dev/log  local0 warning
    chroot      /var/lib/haproxy
    pidfile     /var/run/haproxy.pid
    maxconn     4000
    user        haproxy
    group       haproxy
    daemon
   stats socket /var/lib/haproxy/stats
defaults
  log global
  option  httplog
  option  dontlognull
        timeout connect 5000
        timeout client 50000
        timeout server 50000

#frontend monitor-in
  #bind *:33305
  #mode http
  #option httplog
  #monitor-uri /monitor

frontend kube-apiserver
  bind *:36443
  mode tcp
  option tcplog
  default_backend kube-apiserver

backend kube-apiserver
    mode tcp
    option tcplog
    option tcp-check
    balance roundrobin
    default-server inter 10s downinter 5s rise 2 fall 2 slowstart 60s maxconn 250 maxqueue 256 weight 100
    server kube-apiserver-1 172.22.33.215:6443 check # Replace the IP address with your own.
    server kube-apiserver-2 172.22.33.216:6443 check # Replace the IP address with your own.
    server kube-apiserver-3 172.22.33.217:6443 check # Replace the IP address with your own.
EOF

4.3 启动Haproxy

$ systemctl enable haproxy
$ systemctl start haproxy

6. 部署Kubernetes Master

官方kubeadm 初始化说明：

https://kubernetes.io/zh/docs/reference/setup-tools/kubeadm/kubeadm-init/#config-file
https://kubernetes.io/docs/setup/production-environment/tools/kubeadm/create-cluster-kubeadm/#initializing-your-control-plane-node

6.1 准备好kubeadm-init.yaml初始化文件

6.1.1 kubeadm 初始化

⚠️ kubeadm-init.yam K8S 版本 <= 1.20

#在每个master 节点创建K8S,init 的工作目录
$ mkdir -p /etc/kubernetes/init

$ cat >> etc/kubernetes/init/kubeadm-init.yaml << EOF
---
apiVersion: kubeadm.k8s.io/v1beta2
bootstrapTokens:
- groups:
  - system:bootstrappers:kubeadm:default-node-token
  token: 35sesk.5tm3tqc66tzlse8c
  ttl: 24h0m0s
  usages:
  - signing
  - authentication
kind: InitConfiguration
localAPIEndpoint:
  advertiseAddress: 172.22.33.215     #指定master01 ip地址
  bindPort: 6443
nodeRegistration:
  criSocket: /var/run/dockershim.sock
  name: k8s-master01                  #指定master01主机名
  taints:
  - effect: NoSchedule
    key: node-role.kubernetes.io/master
---
apiServer:
  certSANs:
    - "kubernetes"
    - "kubernetes.default"
    - "kubernetes.default.svc"
    - "kubernetes.default.svc.cluster.local"
    - "172.22.33.210"         #填写所有master节点IP，VIP, 以及公网IP，域名
    - "172.22.33.215"
    - "172.22.33.216"
    - "172.22.33.217"
    - "112.94.71.21"
    - "k8s.srebro.cn"
  timeoutForControlPlane: 4m0s
apiVersion: kubeadm.k8s.io/v1beta2
certificatesDir: /etc/kubernetes/pki
clusterName: kubernetes
controllerManager: {}
controlPlaneEndpoint: "172.22.33.210:36443"   #增加kubeapiserver集群ip地址和端口,就是VIP
dns:
  type: CoreDNS
etcd:
  local:
    dataDir: /var/lib/etcd
imageRepository: registry.aliyuncs.com/google_containers
kind: ClusterConfiguration
kubernetesVersion: v1.20.15
networking:
  dnsDomain: cluster.local
  serviceSubnet: 10.96.0.0/12
  podSubnet: 10.244.0.0/16
scheduler: {}
---
apiVersion: kubeproxy.config.k8s.io/v1alpha1
kind: KubeProxyConfiguration
mode: "ipvs"
EOF

6.2 在所有master 节点上，pull 镜像到本地

init 之前，先下载镜像到master 机器上

#k8s-master01 节点上
$ kubeadm config images pull --config kubeadm-init.yaml

[config/images] Pulled registry.aliyuncs.com/google_containers/kube-apiserver:v1.20.15
[config/images] Pulled registry.aliyuncs.com/google_containers/kube-controller-manager:v1.20.15
[config/images] Pulled registry.aliyuncs.com/google_containers/kube-scheduler:v1.20.15
[config/images] Pulled registry.aliyuncs.com/google_containers/kube-proxy:v1.20.15
[config/images] Pulled registry.aliyuncs.com/google_containers/pause:3.2
[config/images] Pulled registry.aliyuncs.com/google_containers/etcd:3.4.13-0
[config/images] Pulled registry.aliyuncs.com/google_containers/coredns:1.7.0



#k8s-master02 节点上
$ kubeadm config images pull --config kubeadm-init.yaml

[config/images] Pulled registry.aliyuncs.com/google_containers/kube-apiserver:v1.20.15
[config/images] Pulled registry.aliyuncs.com/google_containers/kube-controller-manager:v1.20.15
[config/images] Pulled registry.aliyuncs.com/google_containers/kube-scheduler:v1.20.15
[config/images] Pulled registry.aliyuncs.com/google_containers/kube-proxy:v1.20.15
[config/images] Pulled registry.aliyuncs.com/google_containers/pause:3.2
[config/images] Pulled registry.aliyuncs.com/google_containers/etcd:3.4.13-0
[config/images] Pulled registry.aliyuncs.com/google_containers/coredns:1.7.0


#k8s-master03 节点上
$ kubeadm config images pull --config kubeadm-init.yaml

[config/images] Pulled registry.aliyuncs.com/google_containers/kube-apiserver:v1.20.15
[config/images] Pulled registry.aliyuncs.com/google_containers/kube-controller-manager:v1.20.15
[config/images] Pulled registry.aliyuncs.com/google_containers/kube-scheduler:v1.20.15
[config/images] Pulled registry.aliyuncs.com/google_containers/kube-proxy:v1.20.15
[config/images] Pulled registry.aliyuncs.com/google_containers/pause:3.2
[config/images] Pulled registry.aliyuncs.com/google_containers/etcd:3.4.13-0
[config/images] Pulled registry.aliyuncs.com/google_containers/coredns:1.7.0

6.3 在master01 节点上，完成kubeadm 初始化

$ cd /etc/kubernetes/init
$ kubeadm init --config kubeadm-init.yaml


[init] Using Kubernetes version: v1.20.15
[preflight] Running pre-flight checks
    [WARNING SystemVerification]: this Docker version is not on the list of validated versions: 20.10.18. Latest validated version: 19.03
[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'
[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-master01 kubernetes kubernetes.default kubernetes.default.svc kubernetes.default.svc.cluster.local] and IPs [10.96.0.1 172.22.33.215 172.22.33.216 172.22.33.217 218.94.71.250]
[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-master01 localhost] and IPs [172.22.33.215 127.0.0.1 ::1]
[certs] Generating "etcd/peer" certificate and key
[certs] etcd/peer serving cert is signed for DNS names [k8s-master01 localhost] and IPs [172.22.33.215 127.0.0.1 ::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
[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
[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"
[control-plane] Creating static Pod manifest for "kube-scheduler"
[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 13.003320 seconds
[upload-config] Storing the configuration used in ConfigMap "kubeadm-config" in the "kube-system" Namespace
[kubelet] Creating a ConfigMap "kubelet-config-1.20" 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-master01 as control-plane by adding the labels "node-role.kubernetes.io/master=''" and "node-role.kubernetes.io/control-plane='' (deprecated)"
[mark-control-plane] Marking the node k8s-master01 as control-plane by adding the taints [node-role.kubernetes.io/master:NoSchedule]
[bootstrap-token] Using token: abcdef.0123456789abcdef
[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
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
Alternatively, if you are the root user, you can run:
  export KUBECONFIG=/etc/kubernetes/admin.conf
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/
You can now join any number of control-plane nodes by copying certificate authorities
and service account keys on each node and then running the following as root:
  kubeadm join 172.22.33.210:36443 --token abcdef.0123456789abcdef \
    --discovery-token-ca-cert-hash sha256:1105970dfcca841937c09964e46f3fa14a53672105462e50108d95279ed5dc7c \
    --control-plane 

    
Then you can join any number of worker nodes by running the following on each as root:
kubeadm join 172.22.33.210:36443 --token abcdef.0123456789abcdef \
    --discovery-token-ca-cert-hash sha256:1105970dfcca841937c09964e46f3fa14a53672105462e50108d95279ed5dc7c

拷贝kubectl使用的连接k8s认证文件到默认路径

$ mkdir -p $HOME/.kube
$ sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
$ sudo chown $(id -u):$(id -g) $HOME/.kube/config

6.4 加入 Kubernetes Master 节点

因为我们的K8S集群已经初始化过了，再添加其他master 节点到集群中，首要添加是把已经初始化过的证书拷贝到其他master 节点上

6.4.1 在master02和master03节点复制相关证书

#创建K8S证书工作目录
$ mkdir -p /etc/kubernetes/pki/
$ scp -r 172.22.33.215:/etc/kubernetes/pki/ca.* /etc/kubernetes/pki/
$ scp -r 172.22.33.215:/etc/kubernetes/pki/sa.* /etc/kubernetes/pki/
$ scp -r 172.22.33.215:/etc/kubernetes/pki/front-proxy-ca.* /etc/kubernetes/pki/

#创建ETCD证书工作目录
$ mkdir -p /etc/kubernetes/pki/etcd
$ scp -r 172.22.33.215:/etc/kubernetes/pki/etcd/ca.* /etc/kubernetes/pki/etcd/


#拷贝kube-admin.conf 文件
$ scp -r 172.22.33.215:/etc/kubernetes/admin.conf /etc/kubernetes/

6.4.2 把 master02和master03节点添加到Kubernetes 集群中

使用刚刚 master01 在kubeadm init输出的kubeadm join命令：

#加入控制平面
$  kubeadm join 172.22.33.210:36443 --token abcdef.0123456789abcdef \
    --discovery-token-ca-cert-hash sha256:1105970dfcca841937c09964e46f3fa14a53672105462e50108d95279ed5dc7c \
    --control-plane

6.4.3 在master01节点上查看master节点个数

$ kubectl get node
NAME           STATUS     ROLES                  AGE     VERSION
k8s-master01   NotReady   control-plane,master   8m26s   v1.20.15
k8s-master02   NotReady   control-plane,master   2m54s   v1.20.15
k8s-master03   NotReady   control-plane,master   59s     v1.20.15

可以看到，所有的master 节点都已经加入到集群中了；NotReady是需要等待CNI网络插件安装好

7. 加入Kubernetes Node 节点

官方文档： https://kubernetes.io/docs/reference/setup-tools/kubeadm/kubeadm-join/

在K8S node 节点上操作

k8s-node01	172.22.33.218
k8s-node02	172.22.33.219
k8s-node03	172.22.33.220

使用刚刚master01 在kubeadm init输出的kubeadm join命令：

$ kubeadm join 172.22.33.210:36443 --token abcdef.0123456789abcdef \
    --discovery-token-ca-cert-hash sha256:1105970dfcca841937c09964e46f3fa14a53672105462e50108d95279ed5dc7c

默认token有效期为24小时，当过期之后，该token就不可用了。这时就需要重新创建token，可以直接在master 节点上，使用命令快捷生成：

$ kubeadm token create --print-join-command

8. 部署容器网络（CNI）

https://kubernetes.io/docs/setup/production-environment/tools/kubeadm/create-cluster-kubeadm/#pod-network
:::danger
注意：只需要部署下面其中一个，推荐Calico。
Calico是一个纯三层的数据中心网络方案，Calico支持广泛的平台，包括Kubernetes、OpenStack等。
Calico 在每一个计算节点利用 Linux Kernel 实现了一个高效的虚拟路由器（ vRouter）来负责数据转发，而每个 vRouter 通过 BGP 协议负责把自己上运行的 workload 的路由信息向整个 Calico 网络内传播。
此外，Calico 项目还实现了 Kubernetes 网络策略，提供ACL功能。
https://docs.projectcalico.org/getting-started/kubernetes/quickstart
K8S版本和calico 版本的对应关系
参考链接：https://blog.csdn.net/qq_32596527/article/details/127692734
:::

$ wget https://projectcalico.docs.tigera.io/archive/v3.21/manifests/calico.yaml

下载完后还需要修改里面定义Pod网络（CALICO_IPV4POOL_CIDR），与前面kubeadm init指定的
--pod-network-cidr=10.244.0.0/16 保持一致；默认是 192.168.0.0/16

- name: CALICO_IPV4POOL_CIDR
  value: "10.244.0.0/16"

修改完后应用清单：

$ kubectl apply -f calico.yaml
$ kubectl get pods -n kube-system

查看所有节点，以及pod，svc情况

$ kubectl get nodes
NAME           STATUS   ROLES                  AGE   VERSION
k8s-master01   Ready    control-plane,master   70m   v1.20.15
k8s-master02   Ready    control-plane,master   64m   v1.20.15
k8s-master03   Ready    control-plane,master   62m   v1.20.15
k8s-node01     Ready    <none>                 46m   v1.20.15
k8s-node02     Ready    <none>                 46m   v1.20.15
k8s-node03     Ready    <none>                 46m   v1.20.15

[root@openeuler ~]# kubectl get all -A
NAMESPACE     NAME                                           READY   STATUS    RESTARTS   AGE
default       pod/my-web-6b6c9df775-2p67z                    1/1     Running   0          45m
default       pod/my-web-6b6c9df775-76f8w                    1/1     Running   0          45m
default       pod/my-web-6b6c9df775-t2zrm                    1/1     Running   0          45m
default       pod/my-web-6b6c9df775-zs6db                    1/1     Running   0          45m
kube-system   pod/calico-kube-controllers-5bb48c55fd-vvktf   1/1     Running   0          52m
kube-system   pod/calico-node-7ng4l                          1/1     Running   0          52m
kube-system   pod/calico-node-lrf24                          1/1     Running   0          47m
kube-system   pod/calico-node-qxnxg                          1/1     Running   0          52m
kube-system   pod/calico-node-vwjt4                          1/1     Running   0          52m
kube-system   pod/coredns-7f89b7bc75-cc6gn                   1/1     Running   0          70m
kube-system   pod/coredns-7f89b7bc75-wsg29                   1/1     Running   0          70m
kube-system   pod/etcd-k8s-master01                          1/1     Running   0          70m
kube-system   pod/etcd-k8s-master02                          1/1     Running   0          65m
kube-system   pod/etcd-k8s-master03                          1/1     Running   0          62m
kube-system   pod/kube-apiserver-k8s-master01                1/1     Running   0          70m
kube-system   pod/kube-apiserver-k8s-master02                1/1     Running   0          65m
kube-system   pod/kube-apiserver-k8s-master03                1/1     Running   0          62m
kube-system   pod/kube-controller-manager-k8s-master01       1/1     Running   1          70m
kube-system   pod/kube-controller-manager-k8s-master02       1/1     Running   0          65m
kube-system   pod/kube-controller-manager-k8s-master03       1/1     Running   0          62m
kube-system   pod/kube-proxy-ck9lr                           1/1     Running   0          63m
kube-system   pod/kube-proxy-vzrs8                           1/1     Running   0          65m
kube-system   pod/kube-proxy-wxb78                           1/1     Running   0          70m
kube-system   pod/kube-proxy-z5chd                           1/1     Running   0          47m
kube-system   pod/kube-scheduler-k8s-master01                1/1     Running   1          70m
kube-system   pod/kube-scheduler-k8s-master02                1/1     Running   0          65m
kube-system   pod/kube-scheduler-k8s-master03                1/1     Running   0          62m

NAMESPACE     NAME                 TYPE        CLUSTER-IP   EXTERNAL-IP   PORT(S)                  AGE
default       service/kubernetes   ClusterIP   10.96.0.1    <none>        443/TCP                  70m
kube-system   service/kube-dns     ClusterIP   10.96.0.10   <none>        53/UDP,53/TCP,9153/TCP   70m

NAMESPACE     NAME                         DESIRED   CURRENT   READY   UP-TO-DATE   AVAILABLE   NODE SELECTOR            AGE
kube-system   daemonset.apps/calico-node   4         4         4       4            4           kubernetes.io/os=linux   52m
kube-system   daemonset.apps/kube-proxy    4         4         4       4            4           kubernetes.io/os=linux   70m

NAMESPACE     NAME                                      READY   UP-TO-DATE   AVAILABLE   AGE
default       deployment.apps/my-web                    4/4     4            4           45m
kube-system   deployment.apps/calico-kube-controllers   1/1     1            1           52m
kube-system   deployment.apps/coredns                   2/2     2            2           70m

NAMESPACE     NAME                                                 DESIRED   CURRENT   READY   AGE
default       replicaset.apps/my-web-6b6c9df775                    4         4         4       45m
kube-system   replicaset.apps/calico-kube-controllers-5bb48c55fd   1         1         1       52m
kube-system   replicaset.apps/coredns-7f89b7bc75                   2         2         2       70m

9. 测试kubernetes集群

验证Pod工作
验证Pod网络通信
验证DNS解析

在Kubernetes集群中创建一个pod，验证是否正常运行：

$ kubectl create deployment nginx --image=nginx
$ kubectl expose deployment nginx --port=80 --type=NodePort
$ kubectl get pod,svc

访问地址：http://NodeIP:Port

10. 部署 Dashboard[可选]

$ wget https://raw.githubusercontent.com/kubernetes/dashboard/v2.0.3/aio/deploy/recommended.yaml

默认Dashboard只能集群内部访问，修改Service为NodePort类型，暴露到外部：

$ vi recommended.yaml
...
kind: Service
apiVersion: v1
metadata:
  labels:
    k8s-app: kubernetes-dashboard
  name: kubernetes-dashboard
  namespace: kubernetes-dashboard
spec:
  ports:
    - port: 443
      targetPort: 8443
      nodePort: 30001
  selector:
    k8s-app: kubernetes-dashboard
  type: NodePort
...

$ kubectl apply -f recommended.yaml
$ kubectl get pods -n kubernetes-dashboard
NAME                                         READY   STATUS    RESTARTS   AGE
dashboard-metrics-scraper-6b4884c9d5-gl8nr   1/1     Running   0          13m
kubernetes-dashboard-7f99b75bf4-89cds        1/1     Running   0          13m

访问地址：https://NodeIP:30001
创建service account并绑定默认cluster-admin管理员集群角色：

# 创建用户
$ kubectl create serviceaccount dashboard-admin -n kube-system
# 用户授权
$ kubectl create clusterrolebinding dashboard-admin --clusterrole=cluster-admin --serviceaccount=kube-system:dashboard-admin
# 获取用户Token
$ kubectl describe secrets -n kube-system $(kubectl -n kube-system get secret | awk '/dashboard-admin/{print $1}')

使用输出的token登录Dashboard。

11. 补充

11.1 将节点上的容器运行时从 Docker Engine 改为 containerd

官网参考：https://kubernetes.io/zh-cn/docs/tasks/administer-cluster/migrating-from-dockershim/change-runtime-containerd/
1、配置先决条件【上面环境初始化的时候如果做过了，直接忽略】

$ cat <<EOF | sudo tee /etc/modules-load.d/containerd.conf
overlay
br_netfilter
EOF

$ sudo modprobe overlay
$ sudo modprobe br_netfilter

# 设置必需的 sysctl 参数，这些参数在重新启动后仍然存在。
cat <<EOF | sudo tee /etc/sysctl.d/99-kubernetes-cri.conf
net.bridge.bridge-nf-call-iptables  = 1
net.ipv4.ip_forward                 = 1
net.bridge.bridge-nf-call-ip6tables = 1
EOF

# Apply sysctl params without reboot
$ sudo sysctl --system

2、下线节点

将 <node-to-drain> 替换为你所要下线的节点的名称

kubectl drain <node-to-drain> --ignore-daemonsets

3、停止 Docker 守护进程

systemctl stop kubelet
systemctl disable docker.service --now

4、二进制安装containerd

$ wget https://github.com/containerd/containerd/releases/download/v1.7.20/containerd-1.7.20-linux-amd64.tar.gz
$ tar -xf containerd-1.7.20-linux-amd64.tar.gz

#复制bin下所有二进制文件到/usr/bin 目录下,并覆盖之前的文件
$ cp bin/* /usr/bin/
cp：是否覆盖'/usr/bin/containerd'？ y
cp：是否覆盖'/usr/bin/containerd-shim'？ y
cp：是否覆盖'/usr/bin/containerd-shim-runc-v2'？ y
cp：是否覆盖'/usr/bin/ctr'？ y

#验证containerd的版本
$ containerd --version
containerd github.com/containerd/containerd v1.7.20 8fc6bcff51318944179630522a095cc9dbf9f353


#创建containerd 配置文件
$ mkdir -p /etc/containerd

#也可以使用生成的默认配置
$ containerd config default | sudo tee /etc/containerd/config.toml

修改containerd配置文件

$ cat > /etc/containerd/config.toml << EOF
disabled_plugins = []
imports = []
oom_score = 0
plugin_dir = ""
required_plugins = []
root = "/var/lib/containerd"
state = "/run/containerd"
temp = ""
version = 2

[cgroup]
  path = ""

[debug]
  address = ""
  format = ""
  gid = 0
  level = ""
  uid = 0

[grpc]
  address = "/run/containerd/containerd.sock"
  gid = 0
  max_recv_message_size = 16777216
  max_send_message_size = 16777216
  tcp_address = ""
  tcp_tls_ca = ""
  tcp_tls_cert = ""
  tcp_tls_key = ""
  uid = 0

[metrics]
  address = ""
  grpc_histogram = false

[plugins]

  [plugins."io.containerd.gc.v1.scheduler"]
    deletion_threshold = 0
    mutation_threshold = 100
    pause_threshold = 0.02
    schedule_delay = "0s"
    startup_delay = "100ms"

  [plugins."io.containerd.grpc.v1.cri"]
    device_ownership_from_security_context = false
    disable_apparmor = false
    disable_cgroup = false
    disable_hugetlb_controller = true
    disable_proc_mount = false
    disable_tcp_service = true
    enable_selinux = false
    enable_tls_streaming = false
    enable_unprivileged_icmp = false
    enable_unprivileged_ports = false
    ignore_image_defined_volumes = false
    max_concurrent_downloads = 3
    max_container_log_line_size = 16384
    netns_mounts_under_state_dir = false
    restrict_oom_score_adj = false
    sandbox_image = "registry.aliyuncs.com/google_containers/pause:3.6"
    selinux_category_range = 1024
    stats_collect_period = 10
    stream_idle_timeout = "4h0m0s"
    stream_server_address = "127.0.0.1"
    stream_server_port = "0"
    systemd_cgroup = false
    tolerate_missing_hugetlb_controller = true
    unset_seccomp_profile = ""

    [plugins."io.containerd.grpc.v1.cri".cni]
      bin_dir = "/opt/cni/bin"
      conf_dir = "/etc/cni/net.d"
      conf_template = ""
      ip_pref = ""
      max_conf_num = 1

    [plugins."io.containerd.grpc.v1.cri".containerd]
      default_runtime_name = "runc"
      disable_snapshot_annotations = true
      discard_unpacked_layers = false
      ignore_rdt_not_enabled_errors = false
      no_pivot = false
      snapshotter = "overlayfs"

      [plugins."io.containerd.grpc.v1.cri".containerd.default_runtime]
        base_runtime_spec = ""
        cni_conf_dir = ""
        cni_max_conf_num = 0
        container_annotations = []
        pod_annotations = []
        privileged_without_host_devices = false
        runtime_engine = ""
        runtime_path = ""
        runtime_root = ""
        runtime_type = ""

        [plugins."io.containerd.grpc.v1.cri".containerd.default_runtime.options]

      [plugins."io.containerd.grpc.v1.cri".containerd.runtimes]

        [plugins."io.containerd.grpc.v1.cri".containerd.runtimes.runc]
          base_runtime_spec = ""
          cni_conf_dir = ""
          cni_max_conf_num = 0
          container_annotations = []
          pod_annotations = []
          privileged_without_host_devices = false
          runtime_engine = ""
          runtime_path = ""
          runtime_root = ""
          runtime_type = "io.containerd.runc.v2"

          [plugins."io.containerd.grpc.v1.cri".containerd.runtimes.runc.options]
            BinaryName = ""
            CriuImagePath = ""
            CriuPath = ""
            CriuWorkPath = ""
            IoGid = 0
            IoUid = 0
            NoNewKeyring = false
            NoPivotRoot = false
            Root = ""
            ShimCgroup = ""
            SystemdCgroup = true

    [plugins."io.containerd.grpc.v1.cri".containerd.untrusted_workload_runtime]
      base_runtime_spec = ""
      cni_conf_dir = ""
      cni_max_conf_num = 0
      container_annotations = []
      pod_annotations = []
      privileged_without_host_devices = false
      runtime_engine = ""
      runtime_path = ""
      runtime_root = ""
      runtime_type = ""

      [plugins."io.containerd.grpc.v1.cri".containerd.untrusted_workload_runtime.options]

    [plugins."io.containerd.grpc.v1.cri".image_decryption]
      key_model = "node"

    [plugins."io.containerd.grpc.v1.cri".registry]
      config_path = ""

      [plugins."io.containerd.grpc.v1.cri".registry.auths]

      [plugins."io.containerd.grpc.v1.cri".registry.configs]

      [plugins."io.containerd.grpc.v1.cri".registry.headers]

      [plugins."io.containerd.grpc.v1.cri".registry.mirrors]
        [plugins."io.containerd.grpc.v1.cri".registry.mirrors."docker.io"]
          endpoint = [
            "https://docker.srebro.site"
          ]
        [plugins."io.containerd.grpc.v1.cri".registry.mirrors."gcr.io"]
          endpoint = [
            "https://gcr.srebro.site"
          ]
        [plugins."io.containerd.grpc.v1.cri".registry.mirrors."k8s.gcr.io"]
          endpoint = [
            "https://k8s-gcr.srebro.site"
          ]
        [plugins."io.containerd.grpc.v1.cri".registry.mirrors."quay.io"]
          endpoint = [
            "https://quay.srebro.site"
          ]

    [plugins."io.containerd.grpc.v1.cri".x509_key_pair_streaming]
      tls_cert_file = ""
      tls_key_file = ""

  [plugins."io.containerd.internal.v1.opt"]
    path = "/opt/containerd"

  [plugins."io.containerd.internal.v1.restart"]
    interval = "10s"

  [plugins."io.containerd.internal.v1.tracing"]
    sampling_ratio = 1.0
    service_name = "containerd"

  [plugins."io.containerd.metadata.v1.bolt"]
    content_sharing_policy = "shared"

  [plugins."io.containerd.monitor.v1.cgroups"]
    no_prometheus = false

  [plugins."io.containerd.runtime.v1.linux"]
    no_shim = false
    runtime = "runc"
    runtime_root = ""
    shim = "containerd-shim"
    shim_debug = false

  [plugins."io.containerd.runtime.v2.task"]
    platforms = ["linux/amd64"]
    sched_core = false

  [plugins."io.containerd.service.v1.diff-service"]
    default = ["walking"]

  [plugins."io.containerd.service.v1.tasks-service"]
    rdt_config_file = ""

  [plugins."io.containerd.snapshotter.v1.aufs"]
    root_path = ""

  [plugins."io.containerd.snapshotter.v1.btrfs"]
    root_path = ""

  [plugins."io.containerd.snapshotter.v1.devmapper"]
    async_remove = false
    base_image_size = ""
    discard_blocks = false
    fs_options = ""
    fs_type = ""
    pool_name = ""
    root_path = ""

  [plugins."io.containerd.snapshotter.v1.native"]
    root_path = ""

  [plugins."io.containerd.snapshotter.v1.overlayfs"]
    root_path = ""
    upperdir_label = false

  [plugins."io.containerd.snapshotter.v1.zfs"]
    root_path = ""

  [plugins."io.containerd.tracing.processor.v1.otlp"]
    endpoint = ""
    insecure = false
    protocol = ""

[proxy_plugins]

[stream_processors]

  [stream_processors."io.containerd.ocicrypt.decoder.v1.tar"]
    accepts = ["application/vnd.oci.image.layer.v1.tar+encrypted"]
    args = ["--decryption-keys-path", "/etc/containerd/ocicrypt/keys"]
    env = ["OCICRYPT_KEYPROVIDER_CONFIG=/etc/containerd/ocicrypt/ocicrypt_keyprovider.conf"]
    path = "ctd-decoder"
    returns = "application/vnd.oci.image.layer.v1.tar"

  [stream_processors."io.containerd.ocicrypt.decoder.v1.tar.gzip"]
    accepts = ["application/vnd.oci.image.layer.v1.tar+gzip+encrypted"]
    args = ["--decryption-keys-path", "/etc/containerd/ocicrypt/keys"]
    env = ["OCICRYPT_KEYPROVIDER_CONFIG=/etc/containerd/ocicrypt/ocicrypt_keyprovider.conf"]
    path = "ctd-decoder"
    returns = "application/vnd.oci.image.layer.v1.tar+gzip"

[timeouts]
  "io.containerd.timeout.bolt.open" = "0s"
  "io.containerd.timeout.shim.cleanup" = "5s"
  "io.containerd.timeout.shim.load" = "5s"
  "io.containerd.timeout.shim.shutdown" = "3s"
  "io.containerd.timeout.task.state" = "2s"

[ttrpc]
  address = ""
  gid = 0
  uid = 0
EOF

使用systemd管理containerd ，并启动

$ cat > /etc/systemd/system/containerd.service << EOF

[Unit]
Description=containerd container runtime
Documentation=https://containerd.io
After=network.target

[Service]
ExecStart=/usr/bin/containerd
Restart=always
RestartSec=5
Delegate=yes
KillMode=process
OOMScoreAdjust=-999

[Install]
WantedBy=multi-user.target
EOF


$ systemctl daemon-reload
$ systemctl enable containerd
$ systemctl restart containerd

5、配置kubelet使用containerd并重启kubelet

$ vim /etc/sysconfig/kubelet 
KUBELET_EXTRA_ARGS=--container-runtime=remote --container-runtime-endpoint=unix:///run/containerd/containerd.sock --cgroup-driver=systemd

$ systemctl restart kubelet

6、验证节点处于健康状态

# 会显示出containerd版本，健康状态
$ kubectl get nodes -o wide
NAME         STATUS   ROLES                  AGE     VERSION    INTERNAL-IP     EXTERNAL-IP   OS-IMAGE                    KERNEL-VERSION                        CONTAINER-RUNTIME
k8s-master   Ready    control-plane,master   7d21h   v1.20.15   172.22.33.210   <none>        openEuler 22.03 (LTS-SP4)   5.10.0-221.0.0.124.oe2203sp3.x86_64   containerd://1.7.20
k8s-node1    Ready,SchedulingDisabled    <none>                 7d21h   v1.20.15   172.22.33.211   <none>        openEuler 22.03 (LTS-SP4)   5.10.0-221.0.0.124.oe2203sp3.x86_64   containerd://1.7.20
k8s-node2    Ready    <none>                 7d21h   v1.20.15   172.22.33.212   <none>        openEuler 22.03 (LTS-SP4)   5.10.0-221.0.0.124.oe2203sp3.x86_64   containerd://1.7.20
k8s-node3    Ready    <none>                 6d22h   v1.20.15   172.22.33.213   <none>        openEuler 22.03 (LTS-SP4)   5.10.0-221.0.0.124.oe2203sp3.x86_64   containerd://1.7.20

7、uncordon 节点

将 <node-to-uncordon> 替换为你之前下线的节点的名称。

$ kubectl uncordon <node-to-uncordon>

8、再次验证

[root@k8s-master bin]# kubectl get nodes -o wide
NAME         STATUS   ROLES                  AGE     VERSION    INTERNAL-IP     EXTERNAL-IP   OS-IMAGE                    KERNEL-VERSION                        CONTAINER-RUNTIME
k8s-master   Ready    control-plane,master   7d21h   v1.20.15   172.22.33.210   <none>        openEuler 22.03 (LTS-SP4)   5.10.0-221.0.0.124.oe2203sp3.x86_64   containerd://1.7.20
k8s-node1    Ready    <none>                 7d21h   v1.20.15   172.22.33.211   <none>        openEuler 22.03 (LTS-SP4)   5.10.0-221.0.0.124.oe2203sp3.x86_64   containerd://1.7.20
k8s-node2    Ready    <none>                 7d21h   v1.20.15   172.22.33.212   <none>        openEuler 22.03 (LTS-SP4)   5.10.0-221.0.0.124.oe2203sp3.x86_64   containerd://1.7.20
k8s-node3    Ready    <none>                 6d22h   v1.20.15   172.22.33.213   <none>        openEuler 22.03 (LTS-SP4)   5.10.0-221.0.0.124.oe2203sp3.x86_64   docker://20.10.18

11.2 kubectl 命令补齐

$ yum install bash-completion -y
$ source /usr/share/bash-completion/bash_completion
$ source <(kubectl completion bash)
$ kubectl completion bash >/etc/bash_completion.d/kubectl

本文是原创文章，采用 CC BY-NC-ND 4.0 协议，完整转载请注明来自运维小弟