ubuntu18.04.4安装k8s

k8s部署

1.集群所有主机关闭swap

sudo swapoff -a

sudo sed -i 's/.*swap.*/#&/' /etc/fstab

如果重启后swap还是自动挂载执行systemctl mask dev-sda3.swap（dev-sdax为swap磁盘分区）

2.集群中所有服务器安装docker

sudo apt-get update

sudo apt-get -y install \
apt-transport-https \
ca-certificates \
curl \
gnupg-agent \
software-properties-common

curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo apt-key add -

sudo add-apt-repository \
"deb [arch=amd64] https://download.docker.com/linux/ubuntu \
$(lsb_release -cs) \
stable"

sudo apt-get update

sudo apt-get install -y docker-ce docker-ce-cli containerd.io

3.集群所有节点上安装  kubectl kubelet kubeadm

添加阿里云k8s源

curl -fsSL https://mirrors.aliyun.com/kubernetes/apt/doc/apt-key.gpg | sudo apt-key add -

sudo vim /etc/apt/sources.list

deb https://mirrors.aliyun.com/kubernetes/apt/ kubernetes-xenial main

sudo apt-get update

sudo apt-get -y install kubectl kubelet kubeadm

sudo apt-mark hold kubelet kubeadm kubectl

修改docker Cgroup Driver为systemd

cat <<EOF | sudo tee /etc/docker/daemon.json

{
"exec-opts":["native.cgroupdriver=systemd"]
}

EOF

sudo systemctl restart docker.service

4.初始化master节点

kubeadm init --image-repository registry.aliyuncs.com/google_containers --kubernetes-version v1.18.2 --pod-network-cidr=10.244.0.0/16

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 192.168.0.130:6443 --token 2tun7p.y9ftxhjvwt69djyx \
--discovery-token-ca-cert-hash sha256:63159dd2b07b995894790ec0e7293977b698eccfb9c6b21f1b3a8cb007682e5a

kubectl get nodes

为了使用更便捷，启用 kubectl 命令的自动补全功能。

echo "source <(kubectl completion bash)" >> ~/.bashrc

5.master节点安装flannel网络

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

6.加入node节点

kubeadm join 192.168.0.130:6443 --token 2tun7p.y9ftxhjvwt69djyx \
--discovery-token-ca-cert-hash sha256:63159dd2b07b995894790ec0e7293977b698eccfb9c6b21f1b3a8cb007682e5a

在master上查看node节点

kubectl get nodes

使用label给节点角色打标签

kubectl label node k8s-node01 node-role.kubernetes.io/node=node

journalctl -xeu kubelet查看kubelet日志

默认情况下，token的有效期是24小时，如果我们的token已经过期的话，可以使用以下命令重新生成：

# kubeadm token create
　如果我们也没有--discovery-token-ca-cert-hash的值，可以使用以下命令生成：
# openssl x509 -pubkey -in /etc/kubernetes/pki/ca.crt | openssl rsa -pubin -outform der 2>/dev/null | openssl dgst -sha256 -hex | sed 's/^.* //'

kubeadm reset 可以重置'kubeadm init' or 'kubeadm join'的操作。  同时需要删除家目录下的.kube 目录。才能恢复到初始化之前的状态

安装部署Dashboard

1.在master上下载并修改Dashboard安装脚本

cd ~

mkdir Dashboard

wget https://raw.githubusercontent.com/kubernetes/dashboard/v2.0.1/aio/deploy/recommended.yaml

vim recommended.yaml

-----

#增加直接访问端口

kind: Service
apiVersion: v1
metadata:
labels:
k8s-app: kubernetes-dashboard
name: kubernetes-dashboard
namespace: kubernetes-dashboard
spec:
type: NodePort  #增加
ports:
- port: 443
targetPort: 8443
nodePort: 30000 #增加
selector:
k8s-app: kubernetes-dashboard

---

因为自动生成的证书很多浏览器无法使用，所以我们自己创建，注释掉kubernetes-dashboard-certs对象声明

#apiVersion: v1
#kind: Secret
#metadata:
# labels:
# k8s-app: kubernetes-dashboard
# name: kubernetes-dashboard-certs
# namespace: kubernetes-dashboard
#type: Opaque

2.创建证书

mkdir dashboard-certs

cd dashboard-certs

创建命名空间

kubectl create namespace kubernetes-dashboard

创建key文件

openssl genrsa -out dashboard.key 2048

证书请求

openssl rand -writerand /home/tiny/.rnd

openssl req -new -out dashboard.csr -key dashboard.key -subj '/CN=dashboard-cert'

自签证书

openssl x509 -req -in dashboard.csr -signkey dashboard.key -out dashboard.crt

创建kubernetes-dashboard-certs对象

kubectl create secret generic kubernetes-dashboard-certs --from-file=dashboard.key --from-file=dashboard.crt -n kubernetes-dashboard

3.安装Dashboard

cd ~/Dashboard

kubectl create -f  recommended.yaml

检查结果

kubectl get pods -A  -o wide

kubectl get service -n kubernetes-dashboard  -o wide

4.创建dashboard管理员

创建账号

vim dashboard-admin.yaml

apiVersion: v1
kind: ServiceAccount
metadata:
labels:
k8s-app: kubernetes-dashboard
name: dashboard-admin
namespace: kubernetes-dashboard

kubectl create -f dashboard-admin.yaml

为用户分配权限

vim dashboard-admin-bind-cluster-role.yaml

apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
name: dashboard-admin-bind-cluster-role
labels:
k8s-app: kubernetes-dashboard
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: ClusterRole
name: cluster-admin
subjects:
- kind: ServiceAccount
name: dashboard-admin
namespace: kubernetes-dashboard

kubectl create -f dashboard-admin-bind-cluster-role.yaml

查看并复制用户Token

kubectl -n kubernetes-dashboard describe secret $(kubectl -n kubernetes-dashboard get secret | grep dashboard-admin | awk '{print $1}')

在浏览器中打开链接 https://192.168.0.130:30000

选择Token登录，输入刚才获取到的Token登录。

5.在master上安装metrics-server

cd ~

mkdir metrics-server
cd metrics-server

wget https://github.com/kubernetes-sigs/metrics-server/releases/download/v0.3.6/components.yaml

vim components.yaml

修改image

image: mirrorgooglecontainers/metrics-server-amd64:v0.3.6

添加启动参数

- --kubelet-preferred-address-types=InternalIP
- --kubelet-insecure-tls

kubectl create -f components.yaml

安装完成后可以看到dashboard界面上CPU和内存使用情况了

6.修改登录dashboard Token过期时间，默认15分钟

登录dashboard，修改kubernetes-dashboard配置文件

k8s练习

1.部署应用

kubectl create deployment httpd-app --image=httpd

2.扩容应用

kubectl scale deployment/httpd-app --replicas=2