kubeadm 安装k8s 1.15.1版本详细过程

目录

1.安装k8s依赖环境

2.安装docker

3.安装k8s

---

1.安装k8s依赖环境

• #关闭swap

swapoff -a 

• #注释掉swap行 /etc/fstab
• #查看分区swap，swap都是 0则关闭成功。

free -h

• # 关闭 Selinux

setenforce 0 && sed -i 's/^SELINUX=.*/SELINUX=disabled/' /etc/selinux/config

• #重启，查看关闭否

reboot
getenforce

• #升级内核

rpm -Uvh http://www.elrepo.org/elrepo-release-7.0-3.el7.elrepo.noarch.rpm
# 安装完成后检查 /boot/grub2/grub.cfg 中对应内核 menuentry 中是否包含 新内核 配置，如果没有，再装一次！
yum --enablerepo=elrepo-kernel install -y kernel-lt
#grep menuentry /boot/grub2/grub.cfg 

• #  设置开机从新内核启动 (/boot/grub2/grub.cfg 文件中查找完整的内核版本"CentOS linux (4.4.182-1.el7.elrepo.x86_64) 7 (Core)")

grub2-set-default "CentOS linux (4.4.182-1.el7.elrepo.x86_64) 7 (Core)"
#grub2-set-default 'CentOS Linux (5.4.197-1.el7.elrepo.x86_64) 7 (Core)'
reboot
uname -r

• #另一种针对4.x的安装内核方法

wget http://mirrors.aliyun.com/elrepo/kernel/el7/x86_64/RPMS/kernel-lt-4.4.184-1.el7.elrepo.x86_64.rpm
yum  install  kernel-lt-4.4.184-1.el7.elrepo.x86_64.rpm
awk -F\' '$1=="menuentry " {print i++ " : " $2}' /etc/grub2.cfg
#根据上面查到内核编号，下面设置启动顺序。
grub2-set-default 0  

• 加载内核转发模块，这个k8s网络必须的。

yum install -y ipvsadm
yum install -y conntrack
echo 'modprobe br_netfilter' >>/etc/profile
echo 'modprobe -- ip_vs' >>/etc/profile
echo 'modprobe -- ip_vs_rr' >>/etc/profile
echo 'modprobe -- ip_vs_wrr' >>/etc/profile
echo 'modprobe -- ip_vs_sh' >>/etc/profile
echo 'modprobe -- nf_conntrack' >>/etc/profile

#modprobe -- nf_conntrack_ipv4
#modprobe -- nf_conntrack  如果是内核5.2以上去掉了ipv4的后缀
#验证
reboot
lsmod |grep  -e  ip_vs -e nf_conntrack

• #调整内核参数，对于k8s

#调整这里，先重启下服务器，因为之前的参数没生效，影响这儿了。
cat > /etc/sysctl.d/k8s.conf << EOF
net.bridge.bridge-nf-call-iptables=1
net.bridge.bridge-nf-call-ip6tables=1
net.ipv4.ip_forward=1
#内核4.x以上去掉了这个参数
#net.ipv4.tcp_tw_recycle=0  
vm.swappiness=0
vm.overcommit_memory=1
vm.panic_on_oom=0
fs.inotify.max_user_instances=8192
fs.inotify.max_user_watches=1048576
fs.file-max=52706963
fs.nr_open=52706963
net.ipv6.conf.all.disable_ipv6=1
EOF
sysctl -p /etc/sysctl.d/k8s.conf

2.安装docker

• 需要安装yum扩展工具包

配置docker的下载yum源。注意这个不是docker镜像仓库！！！只是下载docker软件的地址。
#device-mapper-persistent-data lvm2 为docker依赖的包
yum install -y yum-utils device-mapper-persistent-data lvm2
#配置docker默认yum仓库：任选之一
yum-config-manager --add-repo http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo
#yum-config-manager --add-repo https://download.docker.com/linux/centos/docker-ce.repo
#yum-config-manager --add-repo https://mirrors.tuna.tsinghua.edu.cn/docker-ce/linux/centos/docker-ce.repo
#禁用和启用yum仓库，如果要删除，直接删除文件。
# yum-config-manager --disable http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo
# yum-config-manager --enable http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo
#安装docker-ce
yum install docker-ce -y

• 配置docker的日志信息，国内镜像仓库地址

cat > /etc/docker/daemon.json < {
  "exec-opts": ["native.cgroupdriver=systemd"],
  "log-driver": "json-file",
  "log-opts": {
    "max-size": "100m"
  },
  "storage-driver": "overlay2",
  "storage-opts": [
    "overlay2.override_kernel_check=true"
  ],
  "registry-mirrors": ["https://registry.docker-cn.com"]
}
EOF

• #启动

systemctl start docker
systemctl enable docker

• #测试

如果打印一行Hello from Docker! 表示安装完成
docker run hello-world

• #删除所有容器信息都在这个目录

rm -rf /var/lib/docker

• docker日志：

/var/lib/docker/containers/<容器id>/<容器id>-json.log 里面

3.安装k8s

• #安装kubeadm，kubectl，kubelet即安装k8s平台的官方工具，安装kubectl，kubelet k8s 服务器端和客户端 管理插件，安装yum源，默认源没有安装包。

cat < /etc/yum.repos.d/k8s.repo
[k8s]
name=Kubernetes
baseurl=http://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64
enabled=1
gpgcheck=0
EOF
yum clean all  && yum makecache
yum -y install kubeadm-1.15.1 kubectl-1.15.1 kubelet-1.15.1
#开启开启启动（现在无法启动，还没初始化集群）
systemctl enable kubelet

########################################################################################
↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑
以上操作，所有节点都要操作
↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑

• 初始化主节点

#只在主节点操作
#推荐导出配置文件，然后指定配置文件完成初始化，这样可以保留初始化参数。
#默认有许多参数，只需要调整主节点ip，pod网络段，以及kubeproxy支持ipvs模式，版本信息即可。
#初始化时候，会读取hosts去识别主机名字，改了名字记得在这里解析，不然无法启动。
#虚拟机如果cpu只有1核要改2，不然也报错。
kubeadm config print init-defaults > kubeadm-config.yaml

#初始化主节点，过程下载许多镜像，需要等待。
kubeadm init --config=kubeadm-config.yaml --experimental-upload-certs |tee kubeadm-init.log
#初始化报错
#修改docker配置文件"exec-opts": ["native.cgroupdriver=systemd"]
#Environment="KUBELET_KUBECONFIG_ARGS=--bootstrap-kubeconfig=/etc/kubernetes/bootstrap-kubelet.conf --kubeconfig=/etc/kubernetes/kubelet.conf  --cgroup-driver=systemd
#重启两个软件。

#重置初始化
#echo y |kubeadm reset

• 下载网络插件

wget https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
kubectl apply -f kube-flannel.yml

#主节点增加访问控制文件
mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config

• 操作节点，加入集群

kubeadm join 192.168.18.101:6443 --token abcdef.0123456789abcdef \
    --discovery-token-ca-cert-hash sha256:a3a8b8e1ee899c0df1f19887942d71c6412d9de56955e8aa43191ca49d10b961
    
#删除节点
#主节点操作
kubectl delete node c102
#被删除的节点：
rm -f /etc/kubernetes/kubelet.conf
rm -f /etc/kubernetes/pki/ca.crt
rm -f /etc/kubernetes/bootstrap-kubelet.conf
reboot

#从节点加入成功后，可能网络、proxy 容器无法启动，可以把主节点的pause proxy 镜像导入节点
#如果还有节点的容器没有启动成功，可以重新创建它，方法如下：
kubectl get pod  kube-flannel-ds-g85zs -n kube-system  -o yaml >kube-flannel-ds-g85zs.yaml
kubectl delete -f kube-flannel-ds-g85zs.yaml
kubectl apply -f kube-flannel-ds-g85zs.yaml

• 修改集群插件通信证书时间，默认是一年，如果更新版本，会自动更新。
  
  kubeadm alpha certs renew all
  #检查所有证书到期时间。
  kubeadm alpha certs check-expiration

#如果在没网的环境，需要自己手动修改
检查证书时间：
#重新更新所有证书，期限1年

#安装metrics监控模块

用于查看pod使用的服务器的使用率和Hpa自动扩容的基础组件

安装如下所有yaml文件使用命令：kubectl apply -f ./
aggregated-metrics-reader.yaml

kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: system:aggregated-metrics-reader
  labels:
    rbac.authorization.k8s.io/aggregate-to-view: "true"
    rbac.authorization.k8s.io/aggregate-to-edit: "true"
    rbac.authorization.k8s.io/aggregate-to-admin: "true"
rules:
- apiGroups: ["metrics.k8s.io"]
  resources: ["pods", "nodes"]
  verbs: ["get", "list", "watch"]

auth-delegator.yaml

kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: system:aggregated-metrics-reader
  labels:
    rbac.authorization.k8s.io/aggregate-to-view: "true"
    rbac.authorization.k8s.io/aggregate-to-edit: "true"
    rbac.authorization.k8s.io/aggregate-to-admin: "true"
rules:
- apiGroups: ["metrics.k8s.io"]
  resources: ["pods", "nodes"]
  verbs: ["get", "list", "watch"]
[root@c101 1.8+]# cat auth-delegator.yaml
---
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: ClusterRoleBinding
metadata:
  name: metrics-server:system:auth-delegator
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: system:auth-delegator
subjects:
- kind: ServiceAccount
  name: metrics-server
  namespace: kube-system

auth-reader.yaml

apiVersion: rbac.authorization.k8s.io/v1beta1
kind: RoleBinding
metadata:
  name: metrics-server-auth-reader
  namespace: kube-system
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: Role
  name: extension-apiserver-authentication-reader
subjects:
- kind: ServiceAccount
  name: metrics-server
  namespace: kube-system

metrics-apiservice.yaml

apiVersion: apiregistration.k8s.io/v1beta1
kind: APIService
metadata:
  name: v1beta1.metrics.k8s.io
spec:
  service:
    name: metrics-server
    namespace: kube-system
  group: metrics.k8s.io
  version: v1beta1
  insecureSkipTLSVerify: true
  groupPriorityMinimum: 100
  versionPriority: 100

metrics-server-deployment.yaml

apiVersion: v1
kind: ServiceAccount
metadata:
  name: metrics-server
  namespace: kube-system
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: metrics-server
  namespace: kube-system
  labels:
    k8s-app: metrics-server
spec:
  selector:
    matchLabels:
      k8s-app: metrics-server
  template:
    metadata:
      name: metrics-server
      labels:
        k8s-app: metrics-server
    spec:
      serviceAccountName: metrics-server
      volumes:
      # mount in tmp so we can safely use from-scratch images and/or read-only containers
      - name: tmp-dir
        emptyDir: {}
      containers:
      - name: metrics-server
        image: k8s.gcr.io/metrics-server-amd64:v0.3.6
        imagePullPolicy: IfNotPresent
        command:
          - /metrics-server
          - --kubelet-insecure-tls
          - --kubelet-preferred-address-types=InternalIP,Hostname,InternalDNS,ExternalDNS,ExternalIP
          - --metric-resolution=30s
        volumeMounts:
        - name: tmp-dir
          mountPath: /tmp

metrics-server-service.yaml

apiVersion: v1
kind: Service
metadata:
  name: metrics-server
  namespace: kube-system
  labels:
    kubernetes.io/name: "Metrics-server"
    kubernetes.io/cluster-service: "true"
spec:
  selector:
    k8s-app: metrics-server
  ports:
  - port: 443
    protocol: TCP
    targetPort: 443

resource-reader.yaml

apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
  name: system:metrics-server
rules:
- apiGroups:
  - ""
  resources:
  - pods
  - nodes
  - nodes/stats
  - namespaces
  verbs:
  - get
  - list
  - watch
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: system:metrics-server
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: system:metrics-server
subjects:
- kind: ServiceAccount
  name: metrics-server
  namespace: kube-system