ubuntu18.04使用kubeadm部署k8s单节点

实验目的：

 　　体验kubeadm部署k8s服务，全流程体验！

实验环境：

• ubuntu18.04
• 联网在线部署
• kubeadm

01、系统检查

• 节点主机名唯一，建议写入/etc/hosts
• 禁止swap分区
• 关闭防火墙

root@ubuntu:~# hostnamectl set-hostname k8s-master

tail /etc/hosts

192.168.3.101 k8s-master

 root@ubuntu:~# ufw status

Status: inactive

# swapoff -a # 临时
# vim /etc/fstab # 永久

02、docker-ce

# step 1: 安装必要的一些系统工具
apt-get -y install apt-transport-https ca-certificates curl software-properties-common

# step 2: 安装GPG证书
curl -fsSL http://mirrors.aliyun.com/docker-ce/linux/ubuntu/gpg | apt-key add -

# Step 3: 写入软件源信息
add-apt-repository "deb [arch=amd64] http://mirrors.aliyun.com/docker-ce/linux/ubuntu $(lsb_release -cs) stable"

# Step 4: 更新并安装 Docker-CE
apt-get -y update

# 安装指定版本的Docker-CE:
# Step 1: 查找Docker-CE的版本:
apt-cache madison docker-ce

# sudo apt-get -y install docker-ce=[VERSION]   //安装格式

apt-get -y install docker-ce=18.06.3~ce~3-0~ubuntu

###配置docker-hub源
tee /etc/docker/daemon.json <<-'EOF'
{
"registry-mirrors": ["https://dhq9bx4f.mirror.aliyuncs.com"]
}
EOF

systemctl daemon-reload && systemctl restart docker

docker-ce安装请参考阿里云文档：https://yq.aliyun.com/articles/110806

03、kubeadm

 注意：建议kubelet、kubeadm、kubectl 跟kubernetes dashboard最新的支持版本一直

https://github.com/kubernetes/dashboard/releases/tag/v2.0.0-beta4

apt-get update && apt-get install -y apt-transport-https

curl -fsSL https://mirrors.aliyun.com/kubernetes/apt/doc/apt-key.gpg | apt-key add -
#新增源
add-apt-repository "deb [arch=amd64] https://mirrors.aliyun.com/kubernetes/apt/ kubernetes-xenial main"

apt-get update

apt-cache madison kubelet kubectl kubeadm |grep '1.15.4-00'         //查看1.15的最新版本

 apt install -y kubelet=1.15.4-00 kubectl=1.15.4-00 kubeadm=1.15.4-00        //安装指定的版本

 

配置kubelet禁用swap

tee /etc/default/kubelet <<-'EOF'
KUBELET_EXTRA_ARGS="--fail-swap-on=false"
EOF

systemctl daemon-reload && systemctl restart kubelet

注意：目前kubelet服务是启动异常的由于缺少很多参数配置文件，需要等待kubeadm init 后生成，就会自动启动了

 04、初始化k8s

注意： kubeadm初始化捷报：1.13+，阿里云支持镜像拉取  registry.aliyuncs.com/google_containers    //感谢阿里云，提供便利

kubeadm init 
  --kubernetes-version=v1.15.4 
  --image-repository registry.aliyuncs.com/google_containers 
  --pod-network-cidr=10.24.0.0/16 
  --ignore-preflight-errors=Swap

 ###在当前账户下执行，kubectl配置调用

root@k8s-master:~# mkdir -p $HOME/.kube
root@k8s-master:~# cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
root@k8s-master:~# chown $(id -u):$(id -g) $HOME/.kube/config

###k8s网络
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/

https://github.com/coreos/flannel   //用的flannel的overlay 实现多节点pod通信
For Kubernetes v1.7+
kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml

root@k8s-master:~# kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/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-master:~# 
root@k8s-master:~# 
root@k8s-master:~# kubectl get pods -A
NAMESPACE     NAME                                 READY   STATUS     RESTARTS   AGE
kube-system   coredns-bccdc95cf-lnbl9              0/1     Pending    0          2m52s
kube-system   coredns-bccdc95cf-zr8bk              0/1     Pending    0          2m52s
kube-system   etcd-k8s-master                      1/1     Running    0          2m8s
kube-system   kube-apiserver-k8s-master            1/1     Running    0          2m10s
kube-system   kube-controller-manager-k8s-master   1/1     Running    0          2m7s
kube-system   kube-flannel-ds-amd64-wpj2p          0/1     Init:0/1   0          12s     //如果拉取不下来，自己pull就可以
kube-system   kube-proxy-dt9p4                     1/1     Running    0          2m51s
kube-system   kube-scheduler-k8s-master            1/1     Running    0          2m12s

root@ubuntu:~# grep -i image kube-flannel.yml
image: quay.io/coreos/flannel:v0.11.0-amd64
image: quay.io/coreos/flannel:v0.11.0-amd64
image: quay.io/coreos/flannel:v0.11.0-arm64
image: quay.io/coreos/flannel:v0.11.0-arm64
image: quay.io/coreos/flannel:v0.11.0-arm
image: quay.io/coreos/flannel:v0.11.0-arm
image: quay.io/coreos/flannel:v0.11.0-ppc64le
image: quay.io/coreos/flannel:v0.11.0-ppc64le
image: quay.io/coreos/flannel:v0.11.0-s390x
image: quay.io/coreos/flannel:v0.11.0-s390x

docker pull quay.io/coreos/flannel:v0.11.0-amd64

###目前一切正常，image均正常拉取及运行

 ###dashboard

https://github.com/kubernetes/dashboard#kubernetes-dashboard
https://github.com/kubernetes/dashboard/releases

kubectl apply -f https://raw.githubusercontent.com/kubernetes/dashboard/v2.0.0-beta4/aio/deploy/recommended.yaml

root@k8s-master:~# kubectl get pods -A
NAMESPACE              NAME                                        READY   STATUS              RESTARTS   AGE
kube-system            coredns-bccdc95cf-lnbl9                     1/1     Running             0          6m13s
kube-system            coredns-bccdc95cf-zr8bk                     1/1     Running             0          6m13s
kube-system            etcd-k8s-master                             1/1     Running             0          5m29s
kube-system            kube-apiserver-k8s-master                   1/1     Running             0          5m31s
kube-system            kube-controller-manager-k8s-master          1/1     Running             0          5m28s
kube-system            kube-flannel-ds-amd64-wpj2p                 1/1     Running             0          3m33s
kube-system            kube-proxy-dt9p4                            1/1     Running             0          6m12s
kube-system            kube-scheduler-k8s-master                   1/1     Running             0          5m33s
kubernetes-dashboard   dashboard-metrics-scraper-fb986f88d-44wp2   0/1     ContainerCreating   0          32s
kubernetes-dashboard   kubernetes-dashboard-6bb65fcc49-hzzbw       1/1     Running             0          32s
root@k8s-master:~# kubectl get pods -A
NAMESPACE              NAME                                        READY   STATUS    RESTARTS   AGE
kube-system            coredns-bccdc95cf-lnbl9                     1/1     Running   0          6m27s
kube-system            coredns-bccdc95cf-zr8bk                     1/1     Running   0          6m27s
kube-system            etcd-k8s-master                             1/1     Running   0          5m43s
kube-system            kube-apiserver-k8s-master                   1/1     Running   0          5m45s
kube-system            kube-controller-manager-k8s-master          1/1     Running   0          5m42s
kube-system            kube-flannel-ds-amd64-wpj2p                 1/1     Running   0          3m47s
kube-system            kube-proxy-dt9p4                            1/1     Running   0          6m26s
kube-system            kube-scheduler-k8s-master                   1/1     Running   0          5m47s
kubernetes-dashboard   dashboard-metrics-scraper-fb986f88d-44wp2   1/1     Running   0          46s
kubernetes-dashboard   kubernetes-dashboard-6bb65fcc49-hzzbw       1/1     Running   0          46s
root@k8s-master:~# kubectl get namespaces
NAME                   STATUS   AGE
default                Active   7m13s
kube-node-lease        Active   7m17s
kube-public            Active   7m17s
kube-system            Active   7m17s
kubernetes-dashboard   Active   78s

解决kubernetes-dashboard本地打开的问题！！！

具体的可以参考：https://www.cnblogs.com/rainingnight/p/deploying-k8s-dashboard-ui.html

root@k8s-master:~# kubectl cluster-info
Kubernetes master is running at https://192.168.3.101:6443   //apiserver在host暴露的地址
KubeDNS is running at https://192.168.3.101:6443/api/v1/namespaces/kube-system/services/kube-dns:dns/proxy

To further debug and diagnose cluster problems, use 'kubectl cluster-info dump'.

###访问地址

https://<master-ip>:<apiserver-port>/api/v1/namespaces/xxxxxxxx/services/https:kubernetes-dashboard:/proxy/      //请注意namespace

https://192.168.3.101:6443/api/v1/namespaces/kubernetes-dashboard/services/https:kubernetes-dashboard:/proxy/

1.创建服务账号
首先创建一个叫admin-user的服务账号，并放在kube-system名称空间下：
# admin-user.yaml
apiVersion: v1
kind: ServiceAccount
metadata:
  name: admin-user
  namespace: kube-system

执行kubectl create命令：
kubectl create -f admin-user.yaml

2.绑定角色
默认情况下，kubeadm创建集群时已经创建了admin角色，我们直接绑定即可：

# admin-user-role-binding.yaml
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: ClusterRoleBinding
metadata:
  name: admin-user
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: cluster-admin
subjects:
- kind: ServiceAccount
  name: admin-user
  namespace: kube-system
 
执行kubectl create命令：
kubectl create -f  admin-user-role-binding.yaml

3.获取Token
现在我们需要找到新创建的用户的Token，以便用来登录dashboard：

root@k8s-master:~# kubectl -n kube-system describe secret $(kubectl -n kube-system get secret | grep admin-user | awk '{print $
1}')Name: admin-user-token-b9bwj
Namespace: kube-system
Labels: <none>
Annotations: kubernetes.io/service-account.name: admin-user
kubernetes.io/service-account.uid: cf9336ee-2070-49bb-91ee-123b1540cd63

Type: kubernetes.io/service-account-token

Data
====
ca.crt: 1025 bytes
namespace: 11 bytes
token: eyJhbGciOiJSUzI1NiIsImtpZCI6IiJ9.eyJpc3MiOiJrdWJlcm5ldGVzL3NlcnZpY2VhY2NvdW50Iiwia3ViZXJuZXRlcy5pby9zZXJ2aWNlYWNjb3
VudC9uYW1lc3BhY2UiOiJrdWJlLXN5c3RlbSIsImt1YmVybmV0ZXMuaW8vc2VydmljZWFjY291bnQvc2VjcmV0Lm5hbWUiOiJhZG1pbi11c2VyLXRva2VuLWI5YndqIiwia3ViZXJuZXRlcy5pby9zZXJ2aWNlYWNjb3VudC9zZXJ2aWNlLWFjY291bnQubmFtZSI6ImFkbWluLXVzZXIiLCJrdWJlcm5ldGVzLmlvL3NlcnZpY2VhY2NvdW50L3NlcnZpY2UtYWNjb3VudC51aWQiOiJjZjkzMzZlZS0yMDcwLTQ5YmItOTFlZS0xMjNiMTU0MGNkNjMiLCJzdWIiOiJzeXN0ZW06c2VydmljZWFjY291bnQ6a3ViZS1zeXN0ZW06YWRtaW4tdXNlciJ9.nc8N-M0M580d3XdQKkvhj9WEH-7f_kEzkEGSJLmsI1rrlY0a_iGwBTilQ6baFHFKU9ERcW-u8aq85nFHkM7-mJfltAvvbtSbDOr_BUxrP11xvgkCGjPjgnISj1BvAaQlX0IXqpAFEEuJsUUvms9iKlhbF26PbOo1_1DnVnZ1ALlsXcyqoG0-VzbgKuHZPGANJdT17zsfw-xUYWyDBHQhn-BgsryonrwRhZdOWONsy4VH_qyrH3yIv1fazR58Sc4RxU58d1pSTatvCmLWW8AwcMAFfol0lHcZtgMzxecr41sDkySH5eEjWfsDv5OsYFsRoiR_ws65hqUZcjkQ6vclGQ

 ###制作证书

k8s默认启用了RBAC，并为未认证用户赋予了一个默认的身份：anonymous

对于API Server来说，它是使用证书进行认证的，我们需要先创建一个证书：

我们使用client-certificate-data和client-key-data生成一个p12文件，可使用下列命令：

# 生成client-certificate-data
grep 'client-certificate-data' ~/.kube/config | head -n 1 | awk '{print $2}' | base64 -d >> kubecfg.crt

# 生成client-key-data
grep 'client-key-data' ~/.kube/config | head -n 1 | awk '{print $2}' | base64 -d >> kubecfg.key

# 生成p12
openssl pkcs12 -export -clcerts -inkey kubecfg.key -in kubecfg.crt -out kubecfg.p12 -name "kubernetes-client"

下载kubecfg.p12，在window双击安装证书

chrome 打开地址：

https://192.168.3.101:6443/api/v1/namespaces/kubernetes-dashboard/services/https:kubernetes-dashboard:/proxy/     

 注意dashboard的namespaces

进去，输入token即可进入,注意：token的值一行，不要分行

 ###单节点k8s,默认pod不被调度在master节点

kubectl taint nodes --all node-role.kubernetes.io/master-     //去污点，master节点可以被调度

root@k8s-master:~# kubectl taint nodes --all node-role.kubernetes.io/master-  
node/k8s-master untainted

05、测试

在kubernetes-ui上执行yml文件，简单快捷，爽的一笔

执行update,即可在页面创建pod，pod的颜色代表不同的含义，等待拉取部署

总的来说：

　　部署k8s,自己摸索了很久，看着挺简单的，自己搞起来很费劲早起的版本，没有阿里云的支持很难拉取国外的image导致部署不成功！