kubeadm安装部署kubernetes 1.11.3(单主节点)

由于此处docker代理无法使用，因此，请各位设置有效代理进行部署，勿使用文档中的docker代理。整体部署步骤不用改动。谢谢各位支持。

1、部署背景

操作系统版本：CentOS Linux release 7.5. (Core)
docker-ce版本：18.06.-ce
kubernetes版本：1.11.
kubeadm版本：v1.11.3

2、节点划分

master节点：
    主机名：k8s-master-
    ip地址：192.168.40.52
node1节点：
    主机名：k8s-node-
    ip地址：192.168.40.53
node2节点：
    主机名：k8s-node-
    ip地址：192.168.40.54

3、部署前提

、关闭selinux、firewalld。
、开启内核转发。
3、关闭swap交换分区
4、master免密钥登录所有node节点
5、所有节点配置ntp时间同步服务，保证节点时间一致。
6、加载ipvs相关模块

4、集群所有节点初始化

、加载ipvs相关模块以及安装依赖关系
    安装依赖。
    yum install ipset ipvsadm conntrack-tools.x86_64 -y

    加载模块。
    modprobe ip_vs_rr
    modprobe ip_vs_wrr
    modprobe ip_vs_sh
    modprobe ip_vs

    查看模块加载信息。
    lsmod| grep ip_vs

　　　 

、开启内核转发，并使之生效
cat <<EOF | tee /etc/sysctl.d/k8s.conf
net.ipv4.ip_forward =
net.bridge.bridge-nf-call-ip6tables =
net.bridge.bridge-nf-call-iptables =
EOF

sysctl -p /etc/sysctl.d/k8s.conf

、关闭selinux，关闭swap分区，关闭firewalld。

#关闭防火墙，并且禁止自动启动。
systemctl stop firewalld
systemctl disable firewalld

#关闭selinux
sed -i 's#enforcing#disabled#ig' /etc/sysconfig/selinux

#关闭swap分区
swapoff -a && sysctl -w vm.swappiness=0

#修改文件最大打开数量
echo -e '*\tsoft\tnproc\t4096\nroot\tsoft\tnproc\tunlimited' > /etc/security/limits.d/20-nproc.conf
echo -e '* soft nofile 65536\n* hard nofile 65536' > /etc/security/limits.conf

、配置时间同步以及hosts解析，以及实现master节点通过免密钥登录node节点

#安装ntp命令，同时配置任务计划
yum install ntp -y 
任务计划命令如下：
*/5 * * * *  /usr/sbin/ntpdate  0.centos.pool.ntp.org > /dev/null 2> /dev/null

#配置服务器通过hostname可以解析，保证master和node节点上一致,内容如下：
192.168.40.52 k8s-master-52 master
192.168.40.53 k8s-node-53
192.168.40.54 k8s-node-54

#配置master节点通过免秘钥登录node节点
ssh-keygen -t rsa
一路回车，生成公钥和私钥。

ssh-copy-id -i ~/.ssh/id_rsa.pub k8s-node-53
ssh-copy-id -i ~/.ssh/id_rsa.pub k8s-node-54

初始化完成之后，最好能重启服务器。

5、在master节点进行操作

1、配置kubernetes yum源。
vim /etc/yum.repos.d/kubernetes.repo，内容如下：

[kubernetes]
name=kubernetes
baseurl=https://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64/
enabled=
gpgcheck=0

2、配置docker-ce yum源。
yum install -y yum-utils device-mapper-persistent-data lvm2
yum-config-manager --add-repo http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo

3、安装docker-ce、kubernetes。
yum install docker-ce kubelet kubeadm kubectl
软件及依赖的版本如下：
　　

4、配置docker容器代理、启动docker-ce，同时配置docker、kubelet开机自动启动。
配置代理如下：
　　编辑文件：/usr/lib/systemd/system/docker.service
　　Environment="HTTPS_PROXY=http://www.ik8s.io:10080"
　　Environment="NO_PROXY=127.0.0.0/8,192.168.0.0/16"

重新加载相关服务配置。
systemctl daemon-reload

#启动docker
systemctl start docker

#配置docker、kubelet开机自动启动
systemctl enable docker
systemctl enable kubelet

在此处，kubelet不用启动，在kubeadm初始化服务器的时候，初始化完成，会自动启动kubelet服务。

5、初始化master节点
[root@k8s-master-52 ]# kubeadm init --kubernetes-version=v1.11.3 --pod-network-cidr=10.244.0.0/16 --service-cidr=10.96.0.0/12 
命令解析：
　　--kubernetes-version=v1.11.3：指定kubernetes版本
　　--pod-network-cidr=10.244.0.0/16：指定pod网络地址池
　　--service-cidr=10.96.0.0/12：指定service网络地址池

命令执行输出如下:

[init] using Kubernetes version: v1.11.3

[preflight] running pre-flight checks

I0913 20:48:31.926894 2304 kernel_validator.go:81] Validating kernel version

I0913 20:48:31.926940 2304 kernel_validator.go:96] Validating kernel config

  [WARNING SystemVerification]: docker version is greater than the most recently validated version. Docker version: 18.06.1-ce. Max validated version: 17.03

[preflight/images] Pulling images required for setting up a Kubernetes cluster

[preflight/images] This might take a minute or two, depending on the speed of your internet connection

[preflight/images] You can also perform this action in beforehand using 'kubeadm config images pull'

....

中间信息，此处不再给出。根据网络情况，下载镜像，因此初始化的时间不固定。

[addons] Applied essential addon: CoreDNS #1.11版本开始支持coredns，1.10.X版本使用的为kube dns。

[addons] Applied essential addon: kube-proxy

Your Kubernetes master 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/

You can now join any number of machines by running the following on each node

as root:

kubeadm join 192.168.40.52:6443 --token k5mudw.bri3lujvlsxffbqo --discovery-token-ca-cert-hash sha256:f6cf089d5aff3230996f75ca71e74273095c901c1aa45f1325ade0359aeb336e

 

注意：要记住最后一行，kubeadm join这一行的信息，这行信息为node加入集群要执行的命令，请务必复制记录。

 

其中master节点在初始化的时候，会pull docker hub中的镜像。如下：

　　

查看端口占用情况，如下：

　　

其中6443为apiserver的https端口。

从1.11版本开始，默认为ipvs。1.10.X及其之前版本为iptables。

从1.11版本开始支持coredns，1.10.X版本使用的为kube dns。

创建配置文件，使kubectl客户端能正常进行命令进行kubernetes集群的相关操作。

[root@k8s-master-52 ]# mkdir -p $HOME/.kube

[root@k8s-master-52 ]# cp -i /etc/kubernetes/admin.conf $HOME/.kube/config

 

查看集群状态信息。

[root@k8s-master-52 manifests]# kubectl get cs

NAME STATUS MESSAGE ERROR

scheduler Healthy ok

controller-manager Healthy ok

etcd-0 Healthy {"health": "true"}

查看集群节点信息。

[root@k8s-master-52 manifests]# kubectl get nodes

NAME STATUS ROLES AGE VERSION

k8s-master-52 NotReady master 12m v1.11.3

未安装网络组件造成节点status状态为notready。

 

6、安装flannel网络插件。

#直接引用官方的部署模板文件进行安装。

[root@k8s-master-52 ]# kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml

    clusterrole.rbac.authorization.k8s.io/flannel created

    clusterrolebinding.rbac.authorization.k8s.io/flannel created

    serviceaccount/flannel created

    configmap/kube-flannel-cfg created

    daemonset.extensions/kube-flannel-ds-amd64 created

    daemonset.extensions/kube-flannel-ds-arm64 created

    daemonset.extensions/kube-flannel-ds-arm created

    daemonset.extensions/kube-flannel-ds-ppc64le created

    daemonset.extensions/kube-flannel-ds-s390x created

 

[root@k8s-master-52 ]# kubectl get pods -n kube-system

　　

只有等到flannel镜像下载完成，pods才能正常启动。 

6、在node节点操作

、配置kubernetes yum源。
vim /etc/yum.repos.d/kubernetes.repo，内容如下：

[kubernetes]
name=kubernetes
baseurl=https://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64/
enabled=
gpgcheck=

、配置docker-ce yum源。
yum install -y yum-utils device-mapper-persistent-data lvm2
yum-config-manager --add-repo http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo

、安装docker-ce、kubernetes。
yum install docker-ce kubelet kubeadm kubectl
软件及依赖的版本如下：
　　

、配置docker容器代理、启动docker-ce，同时配置docker、kubelet开机自动启动。
配置代理如下：
　　编辑文件：/usr/lib/systemd/system/docker.service
　　Environment="HTTPS_PROXY=http://www.ik8s.io:10080"
　　Environment="NO_PROXY=127.0.0.0/8,192.168.0.0/16"

重新加载相关服务配置。
systemctl daemon-reload

#启动docker
systemctl start docker

#配置docker、kubelet开机自动启动
systemctl enable docker
systemctl enable kubelet
在此处，kubelet不用启动，在kubeadm初始化服务器的时候，初始化完成，会自动启动kubelet服务。

5、安装flannel网络插件。

#直接引用官方的部署模板文件进行安装。

 

在k8s-node-53节点上进行安装。

[root@k8s-node-53 ]# kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml

clusterrole.rbac.authorization.k8s.io/flannel created

clusterrolebinding.rbac.authorization.k8s.io/flannel created

serviceaccount/flannel created

configmap/kube-flannel-cfg created

daemonset.extensions/kube-flannel-ds-amd64 created

daemonset.extensions/kube-flannel-ds-arm64 created

daemonset.extensions/kube-flannel-ds-arm created

daemonset.extensions/kube-flannel-ds-ppc64le created

daemonset.extensions/kube-flannel-ds-s390x created

 　　

在k8s-node-54节点上进行安装。

[root@k8s-node-54 ]# kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml

clusterrole.rbac.authorization.k8s.io/flannel created

clusterrolebinding.rbac.authorization.k8s.io/flannel created

serviceaccount/flannel created

configmap/kube-flannel-cfg created

daemonset.extensions/kube-flannel-ds-amd64 created

daemonset.extensions/kube-flannel-ds-arm64 created

daemonset.extensions/kube-flannel-ds-arm created

daemonset.extensions/kube-flannel-ds-ppc64le created

daemonset.extensions/kube-flannel-ds-s390x created

 

将k8s-node-53节点加入k8s集群。

[root@k8s-node-53 ~]# kubeadm join 192.168.40.52:6443 --token k5mudw.bri3lujvlsxffbqo --discovery-token-ca-cert-hash sha256:f6cf089d5aff3230996f75ca71e74273095c901c1aa45f1325ade0359aeb336e
[preflight] running pre-flight checks
[WARNING RequiredIPVSKernelModulesAvailable]: the IPVS proxier will not be used, because the following required kernel modules are not loaded: [ip_vs_sh ip_vs ip_vs_rr ip_vs_wrr] or no builtin kernel ipvs support: map[ip_vs_wrr:{} ip_vs_sh:{} nf_conntrack_ipv4:{} ip_vs:{} ip_vs_rr:{}]
you can solve this problem with following methods:
1. Run 'modprobe -- ' to load missing kernel modules;
2. Provide the missing builtin kernel ipvs support

I0913 21:13:20.983878 1794 kernel_validator.go:81] Validating kernel version
I0913 21:13:20.983943 1794 kernel_validator.go:96] Validating kernel config
[WARNING SystemVerification]: docker version is greater than the most recently validated version. Docker version: 18.06.1-ce. Max validated version: 17.03
[discovery] Trying to connect to API Server "192.168.40.52:6443"
[discovery] Created cluster-info discovery client, requesting info from "https://192.168.40.52:6443"
[discovery] Requesting info from "https://192.168.40.52:6443" again to validate TLS against the pinned public key
[discovery] Cluster info signature and contents are valid and TLS certificate validates against pinned roots, will use API Server "192.168.40.52:6443"
[discovery] Successfully established connection with API Server "192.168.40.52:6443"
[kubelet] Downloading configuration for the kubelet from the "kubelet-config-1.11" ConfigMap in the kube-system namespace
[kubelet] Writing kubelet configuration to file "/var/lib/kubelet/config.yaml"
[kubelet] Writing kubelet environment file with flags to file "/var/lib/kubelet/kubeadm-flags.env"
[preflight] Activating the kubelet service
[tlsbootstrap] Waiting for the kubelet to perform the TLS Bootstrap...
[patchnode] Uploading the CRI Socket information "/var/run/dockershim.sock" to the Node API object "k8s-node-53" as an annotation

This node has joined the cluster:
* Certificate signing request was sent to master and a response
was received.
* The Kubelet was informed of the new secure connection details.

Run 'kubectl get nodes' on the master to see this node join the cluster.

将k8s-node-54节点加入k8s集群。

[root@k8s-node-54 ~]# kubeadm join 192.168.40.52:6443 --token k5mudw.bri3lujvlsxffbqo --discovery-token-ca-cert-hash sha256:f6cf089d5aff3230996f75ca71e74273095c901c1aa45f1325ade0359aeb336e
[preflight] running pre-flight checks
[WARNING RequiredIPVSKernelModulesAvailable]: the IPVS proxier will not be used, because the following required kernel modules are not loaded: [ip_vs_sh ip_vs ip_vs_rr ip_vs_wrr] or no builtin kernel ipvs support: map[ip_vs:{} ip_vs_rr:{} ip_vs_wrr:{} ip_vs_sh:{} nf_conntrack_ipv4:{}]
you can solve this problem with following methods:
1. Run 'modprobe -- ' to load missing kernel modules;
2. Provide the missing builtin kernel ipvs support

I0913 21:21:03.915755 11043 kernel_validator.go:81] Validating kernel version
I0913 21:21:03.915806 11043 kernel_validator.go:96] Validating kernel config
[WARNING SystemVerification]: docker version is greater than the most recently validated version. Docker version: 18.06.1-ce. Max validated version: 17.03
[discovery] Trying to connect to API Server "192.168.40.52:6443"
[discovery] Created cluster-info discovery client, requesting info from "https://192.168.40.52:6443"
[discovery] Requesting info from "https://192.168.40.52:6443" again to validate TLS against the pinned public key
[discovery] Cluster info signature and contents are valid and TLS certificate validates against pinned roots, will use API Server "192.168.40.52:6443"
[discovery] Successfully established connection with API Server "192.168.40.52:6443"
[kubelet] Downloading configuration for the kubelet from the "kubelet-config-1.11" ConfigMap in the kube-system namespace
[kubelet] Writing kubelet configuration to file "/var/lib/kubelet/config.yaml"
[kubelet] Writing kubelet environment file with flags to file "/var/lib/kubelet/kubeadm-flags.env"
[preflight] Activating the kubelet service
[tlsbootstrap] Waiting for the kubelet to perform the TLS Bootstrap...
[patchnode] Uploading the CRI Socket information "/var/run/dockershim.sock" to the Node API object "k8s-node-54" as an annotation

This node has joined the cluster:
* Certificate signing request was sent to master and a response
was received.
* The Kubelet was informed of the new secure connection details.

Run 'kubectl get nodes' on the master to see this node join the cluster.

7、创建角色，使用k8s dashboard查看集群状态。

vim dashboard-admin.yaml
内容如下：
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: ClusterRoleBinding
metadata:
  name: kubernetes-dashboard
  labels:
    k8s-app: kubernetes-dashboard
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: cluster-admin
subjects:
- kind: ServiceAccount
  name: kubernetes-dashboard
  namespace: kube-system

执行以下命令创建角色：

kubectl create -f dashboard-admin.yaml

8、安装k8s dashboard

vim kubernetes-dashboard.yaml
内容如下：
apiVersion: v1
kind: Secret
metadata:
  labels:
    k8s-app: kubernetes-dashboard
  name: kubernetes-dashboard-certs
  namespace: kube-system
type: Opaque

---
# ------------------- Dashboard Service Account ------------------- #

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

---
# ------------------- Dashboard Role & Role Binding ------------------- #

kind: Role
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: kubernetes-dashboard-minimal
  namespace: kube-system
rules:
  # Allow Dashboard to create 'kubernetes-dashboard-key-holder' secret.
- apiGroups: [""]
  resources: ["secrets"]
  verbs: ["create"]
  # Allow Dashboard to create 'kubernetes-dashboard-settings' config map.
- apiGroups: [""]
  resources: ["configmaps"]
  verbs: ["create"]
  # Allow Dashboard to get, update and delete Dashboard exclusive secrets.
- apiGroups: [""]
  resources: ["secrets"]
  resourceNames: ["kubernetes-dashboard-key-holder", "kubernetes-dashboard-certs"]
  verbs: ["get", "update", "delete"]
  # Allow Dashboard to get and update 'kubernetes-dashboard-settings' config map.
- apiGroups: [""]
  resources: ["configmaps"]
  resourceNames: ["kubernetes-dashboard-settings"]
  verbs: ["get", "update"]
  # Allow Dashboard to get metrics from heapster.
- apiGroups: [""]
  resources: ["services"]
  resourceNames: ["heapster"]
  verbs: ["proxy"]
- apiGroups: [""]
  resources: ["services/proxy"]
  resourceNames: ["heapster", "http:heapster:", "https:heapster:"]
  verbs: ["get"]

---
apiVersion: rbac.authorization.k8s.io/v1
kind: RoleBinding
metadata:
  name: kubernetes-dashboard-minimal
  namespace: kube-system
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: Role
  name: kubernetes-dashboard-minimal
subjects:
- kind: ServiceAccount
  name: kubernetes-dashboard
  namespace: kube-system

---
# ------------------- Dashboard Deployment ------------------- #

kind: Deployment
apiVersion: apps/v1beta2
metadata:
  labels:
    k8s-app: kubernetes-dashboard
  name: kubernetes-dashboard
  namespace: kube-system
spec:
  replicas: 1
  revisionHistoryLimit: 10
  selector:
    matchLabels:
      k8s-app: kubernetes-dashboard
  template:
    metadata:
      labels:
        k8s-app: kubernetes-dashboard
    spec:
      containers:
      - name: kubernetes-dashboard
        image: k8s.gcr.io/kubernetes-dashboard-amd64:v1.10.0
        ports:
        - containerPort: 8443
          protocol: TCP
        args:
          - --auto-generate-certificates
          # Uncomment the following line to manually specify Kubernetes API server Host
          # If not specified, Dashboard will attempt to auto discover the API server and connect
          # to it. Uncomment only if the default does not work.
          # - --apiserver-host=http://my-address:port
        volumeMounts:
        - name: kubernetes-dashboard-certs
          mountPath: /certs
          # Create on-disk volume to store exec logs
        - mountPath: /tmp
          name: tmp-volume
        livenessProbe:
          httpGet:
            scheme: HTTPS
            path: /
            port: 8443
          initialDelaySeconds: 30
          timeoutSeconds: 30
      volumes:
      - name: kubernetes-dashboard-certs
        secret:
          secretName: kubernetes-dashboard-certs
      - name: tmp-volume
        emptyDir: {}
      serviceAccountName: kubernetes-dashboard
      # Comment the following tolerations if Dashboard must not be deployed on master
      tolerations:
      - key: node-role.kubernetes.io/master
        effect: NoSchedule

---
# ------------------- Dashboard Service ------------------- #

kind: Service
apiVersion: v1
metadata:
  labels:
    k8s-app: kubernetes-dashboard
  name: kubernetes-dashboard
  namespace: kube-system
spec:
  type: NodePort
  ports:
    - port: 443
      targetPort: 8443
      nodePort: 30001
  selector:
    k8s-app: kubernetes-dashboard

执行以下命令安装dashboard：

kubectl apply -f  kubernetes-dashboard.yaml 

访问dashboard url如下：

https://192.168.40.54:30001
此处使用集群中任一节点ip，即可访问dashboard页面。

9、生成token认证文件

在主节点上进行执行。

[root@k8s-master-52 opt]# kubectl -n kube-system describe secret $(kubectl -n kube-system get secret | grep admin-user | awk '{print $1}')
Name: admin-user-token-hddfq
Namespace: kube-system
Labels: <none>
Annotations: kubernetes.io/service-account.name=admin-user
kubernetes.io/service-account.uid=2d23955c-b75d-11e8-a770-5254007ec152

Type: kubernetes.io/service-account-token

Data
====
ca.crt: 1025 bytes
namespace: 11 bytes
token: eyJhbGciOiJSUzI1NiIsImtpZCI6IiJ9.eyJpc3MiOiJrdWJlcm5ldGVzL3NlcnZpY2VhY2NvdW50Iiwia3ViZXJuZXRlcy5pby9zZXJ2aWNlYWNjb3VudC9uYW1lc3BhY2UiOiJrdWJlLXN5c3RlbSIsImt1YmVybmV0ZXMuaW8vc2VydmljZWFjY291bnQvc2VjcmV0Lm5hbWUiOiJhZG1pbi11c2VyLXRva2VuLWhkZGZxIiwia3ViZXJuZXRlcy5pby9zZXJ2aWNlYWNjb3VudC9zZXJ2aWNlLWFjY291bnQubmFtZSI6ImFkbWluLXVzZXIiLCJrdWJlcm5ldGVzLmlvL3NlcnZpY2VhY2NvdW50L3NlcnZpY2UtYWNjb3VudC51aWQiOiIyZDIzOTU1Yy1iNzVkLTExZTgtYTc3MC01MjU0MDA3ZWMxNTIiLCJzdWIiOiJzeXN0ZW06c2VydmljZWFjY291bnQ6a3ViZS1zeXN0ZW06YWRtaW4tdXNlciJ9.5GakSIdKw7H62P5Bk3c8879Jc68cAN9gcQRMYvaWLo-Cq6cwnpOoz6fwYm1AoFRfJ_ddMoctqB_rp72j_AqSO0ihp3_H_1dX31bo_ddp1xtj5Yg3IswhcxU2RCBmoIn0JmgCeWxoIt_KAYpNJBJqJKR5oIS2hr_Xfew5GNXRC6_OE9fm7ljRy4XqkBTaj6_1K0wUrmoC4WFHQGZzTUq6mmVsJlD_o3J35sMzi993WtP0APeBc6v66RokHW5EAECN9__ipA9cQlqmtLkgFydORMvUmd4bOWNFoNticx_M6poDlzTLRqmKY5I3mxJmhCCHr2gp7X0auo1enLW765t-7g

使用最后生成的token认证内容登录dashboard。