使用kubeadm安装K8s

初始化master

初始化k8s并锁定v1.17.0版本。

kubeadm init \
--image-repository registry.cn-hangzhou.aliyuncs.com/google_containers \
--kubernetes-version v1.17.0 \
--pod-network-cidr=10.244.0.0/16

下载完成后使用【docker images】命令查看镜像，然后打上标签

docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/kube-proxy:v1.17.0 k8s.gcr.io/kube-proxy:v1.17.0
docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/kube-controller-manager:v1.17.0 k8s.gcr.io/kube-controller-manager:v1.17.0
docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/kube-apiserver:v1.17.0 k8s.gcr.io/kube-apiserver:v1.17.0
docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/kube-scheduler:v1.17.0 k8s.gcr.io/kube-scheduler:v1.17.0
docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/coredns:v1.17.0 k8s.gcr.io/coredns:v1.17.0
docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/coredns:1.6.5 k8s.gcr.io/coredns:1.6.5
docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/etcd:3.4.3-0 k8s.gcr.io/etcd:3.4.3-0
docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/pause:3.1 k8s.gcr.io/pause:3.1

重新执行kubeadm init操作，此时报错

The connection to the server :6443 was refused - did you specify the right host or port?

执行【kubeadm reset】即可。

W1215 21:37:47.571117    2663 validation.go:28] Cannot validate kube-proxy config - no validator is available
W1215 21:37:47.571186    2663 validation.go:28] Cannot validate kubelet config - no validator is available
[init] Using Kubernetes version: v1.17.0
[preflight] Running pre-flight checks
        [WARNING IsDockerSystemdCheck]: detected "cgroupfs" as the Docker cgroup driver. The recommended driver is "systemd". Please follow the guide at https://kubernetes.io/docs/setup/cri/
[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'
[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
[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 [localhost.localdomain kubernetes kubernetes.default kubernetes.default.svc kubernetes.default.svc.cluster.local] and IPs [10.96.0.1 192.168.125.58]
[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 [localhost.localdomain localhost] and IPs [192.168.125.58 127.0.0.1 ::1]
[certs] Generating "etcd/peer" certificate and key
[certs] etcd/peer serving cert is signed for DNS names [localhost.localdomain localhost] and IPs [192.168.125.58 127.0.0.1 ::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
[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"
W1215 21:37:55.230428    2663 manifests.go:214] the default kube-apiserver authorization-mode is "Node,RBAC"; using "Node,RBAC"
[control-plane] Creating static Pod manifest for "kube-scheduler"
W1215 21:37:55.233799    2663 manifests.go:214] the default kube-apiserver authorization-mode is "Node,RBAC"; using "Node,RBAC"
[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 29.729964 seconds
[upload-config] Storing the configuration used in ConfigMap "kubeadm-config" in the "kube-system" Namespace
[kubelet-check] Initial timeout of 40s passed.
[kubelet] Creating a ConfigMap "kubelet-config-1.17" 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 localhost.localdomain as control-plane by adding the label "node-role.kubernetes.io/master=''"
[mark-control-plane] Marking the node localhost.localdomain as control-plane by adding the taints [node-role.kubernetes.io/master:NoSchedule]
[bootstrap-token] Using token: gvn5ya.2bh36o4adqp5rrni
[bootstrap-token] Configuring bootstrap tokens, cluster-info ConfigMap, RBAC Roles
[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

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 192.168.125.58:6443 --token mu4mmq.pdfqfe6pms0m98gd \
    --discovery-token-ca-cert-hash sha256:ce2afa1b29a373970f93bc62c3ae213e95d45e88effa0f3bbbdf7a312c24ea22 

配置KUBECONFIG环境变量

cp -f /etc/kubernetes/admin.conf $HOME/
chown $(id -u):$(id -g) $HOME/admin.conf
export KUBECONFIG=$HOME/admin.conf
echo "export KUBECONFIG=$HOME/admin.conf" >>  ~/.bash_profile

允许master运行pod

kubectl taint nodes --all node-role.kubernetes.io/master-

 

添加node

在从主机执行命令

kubeadm join 192.168.125.58:6443 --token mu4mmq.pdfqfe6pms0m98gd \
    --discovery-token-ca-cert-hash sha256:ce2afa1b29a373970f93bc62c3ae213e95d45e88effa0f3bbbdf7a312c24ea22 

查看pod运行情况

[root@localhost ~]# kubectl get pod -n kube-system
NAME                                            READY   STATUS             RESTARTS   AGE
coredns-6955765f44-d9mtm                        1/1     Running            2          2d1h
coredns-6955765f44-tctz9                        1/1     Running            2          2d1h
etcd-localhost.localdomain                      1/1     Running            3          2d1h
kube-apiserver-localhost.localdomain            1/1     Running            3          2d1h
kube-controller-manager-localhost.localdomain   1/1     Running            42         2d1h
kube-flannel-ds-amd64-mxk57                     1/1     Running            2          25h
kube-flannel-ds-amd64-rd9gj                     0/1     Pending            0          25h
kube-flannel-ds-amd64-w6jhv                     0/1     Pending            0          25h
kube-proxy-j6429                                0/1     ImagePullBackOff   0          2d1h
kube-proxy-tnhh8                                0/1     ImagePullBackOff   0          2d1h
kube-proxy-zw4pq                                1/1     Running            3          2d1h
kube-scheduler-localhost.localdomain            1/1     Running            41         2d1h

安装flannel

先查看当前node

[root@localhost ~]# kubectl get node
  NAME                    STATUS     ROLES    AGE   VERSION
  host1                   NotReady      23h   v1.17.0
  host2                   NotReady      23h   v1.17.0
  localhost.localdomain   NotReady   master   24h   v1.17.0

因为国内下载不了k8s的镜像，所以需要通过下列方式构建镜像：

kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
curl -sSL "https://github.com/coreos/flannel/blob/master/Documentation/kube-flannel.yml?raw=true" | kubectl create -f -

此时再次查看，master节点变为Ready状态说明成功。

[root@localhost ~]# kubectl get node
  NAME                    STATUS     ROLES    AGE   VERSION
  host1                   NotReady      23h   v1.17.0
  host2                   NotReady      23h   v1.17.0
  localhost.localdomain   Ready      master   24h   v1.17.0

安装dashboard

执行下面的命令： 

kubectl apply -f http://mirror.faasx.com/kubernetes/dashboard/master/src/deploy/recommended/kubernetes-dashboard.yaml

此时会报错：error: unable to recognize "http://mirror.faasx.com/kubernetes/dashboard/master/src/deploy/recommended/kubernetes-dashboard.yaml": no matches for kind "Deployment" in version "apps/v1beta2"

百度后说需要把 apps/v1beta2 去掉beta2，实践证明是成功的，把kubernetes-dashboard.yaml下载到本地改就行。

[root@localhost ~]# kubectl get pod -n kube-system
NAME                                            READY   STATUS             RESTARTS   AGE
coredns-6955765f44-d9mtm                        1/1     Running            2          2d1h
coredns-6955765f44-tctz9                        1/1     Running            2          2d1h
etcd-localhost.localdomain                      1/1     Running            3          2d1h
kube-apiserver-localhost.localdomain            1/1     Running            3          2d1h
kube-controller-manager-localhost.localdomain   1/1     Running            42         2d1h
kube-flannel-ds-amd64-mxk57                     1/1     Running            2          25h
kube-flannel-ds-amd64-rd9gj                     0/1     Pending            0          25h
kube-flannel-ds-amd64-w6jhv                     0/1     Pending            0          25h
kube-proxy-j6429                                0/1     ImagePullBackOff   0          2d1h
kube-proxy-tnhh8                                0/1     ImagePullBackOff   0          2d1h
kube-proxy-zw4pq                                1/1     Running            3          2d1h
kube-scheduler-localhost.localdomain            1/1     Running            41         2d1h
kubernetes-dashboard-6ddc5f4f97-4f6sb           1/1     Running            2          23h

启动容器后，我们需要暴露服务

[root@localhost ~]# kubectl get svc -n kube-system
NAME                   TYPE        CLUSTER-IP     EXTERNAL-IP   PORT(S)                  AGE
kube-dns               ClusterIP   10.96.0.10             53/UDP,53/TCP,9153/TCP   2d1h
kubernetes-dashboard   NodePort    10.96.65.147           443/TCP                    24h

为了方便访问，我们把kubernetes-dashboard暴露给nodePort

[root@localhost ~]# kubectl edit svc kubernetes-dashboard  -n kube-system 
# Please edit the object below. Lines beginning with a '#' will be ignored,
# and an empty file will abort the edit. If an error occurs while saving this file will be
# reopened with the relevant failures.
#
apiVersion: v1
kind: Service
metadata:
  annotations:
    kubectl.kubernetes.io/last-applied-configuration: |
      {"apiVersion":"v1","kind":"Service","metadata":{"annotations":{},"labels":{"k8s-app":"kubernetes-dashboard"},"name":"kubernetes-dashboard","namespace":"kube-system"},"spec":{"ports":[{"port":443,"targetPort":8443}],"selector":{"k8s-app":"kubernetes-dashboard"}}}
  creationTimestamp: "2019-12-16T15:22:02Z"
  labels:
    k8s-app: kubernetes-dashboard
  name: kubernetes-dashboard
  namespace: kube-system
  resourceVersion: "30670"
  selfLink: /api/v1/namespaces/kube-system/services/kubernetes-dashboard
  uid: dd167a41-b2b0-4c32-a727-8fbf41fe32be
spec:
  clusterIP: 10.96.65.147
  externalTrafficPolicy: Cluster
  ports:
  - nodePort: 31307
    port: 443
    protocol: TCP
    targetPort: 8443
  selector:
    k8s-app: kubernetes-dashboard
  sessionAffinity: None
  type: NodePort
status:
  loadBalancer: {}

此时再查看pod，可以看到对外暴露了端口：

[root@localhost ~]# kubectl get svc -n kube-system
NAME                   TYPE        CLUSTER-IP     EXTERNAL-IP   PORT(S)                  AGE
kube-dns               ClusterIP   10.96.0.10             53/UDP,53/TCP,9153/TCP   2d1h
kubernetes-dashboard   NodePort    10.96.65.147           443:31307/TCP            24h

如图所示，我们进入登录页面： 

1.创建账号

我们首先创建一个admin的账号，并放在kube-system名称空间下

[root@localhost k8s]# vi admin.yaml
#admin.yaml

apiVersion: v1
kind: ServiceAccount
metadata:
  name: admin
  namespace: kube-system

[root@localhost k8s]# kubectl create -f admin.yaml
serviceaccount/admin created

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

[root@localhost k8s]# kubectl create -f admin.yaml
serviceaccount/admin created
[root@localhost k8s]# vi admin-role-binding.yaml
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: ClusterRoleBinding
metadata:
  name: admin
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: cluster-admin
subjects:
- kind: ServiceAccount
  name: admin
  namespace: kube-system

[root@localhost k8s]# kubectl create -f  admin-role-binding.yaml
clusterrolebinding.rbac.authorization.k8s.io/admin created

3.获取Token

[root@localhost k8s]# kubectl -n kube-system describe secret $(kubectl -n kube-system get secret | grep admin | awk '{print $1}')
Name:         admin-token-nwgp7
Namespace:    kube-system
Labels:       
Annotations:  kubernetes.io/service-account.name: admin
              kubernetes.io/service-account.uid: d7786423-5881-486f-9bfc-70485393763d

Type:  kubernetes.io/service-account-token

Data
====
token:      eyJhbGciOiJSUzI1NiIsImtpZCI6IlFpSFN0eGZEMXVXNldGcG15MWRMQm1mbmtEazVPVlBBNVZHaW5MakJqU28if
Q.eyJpc3MiOiJrdWJlcm5ldGVzL3NlcnZpY2VhY2NvdW50Iiwia3ViZXJuZXRlcy5pby9zZXJ2aWNlYWNjb3VudC9
uYW1lc3BhY2UiOiJrdWJlLXN5c3RlbSIsImt1YmVybmV0ZXMuaW8vc2VydmljZWFjY291bnQvc2VjcmV0Lm5hbWUi
OiJhZG1pbi10b2tlbi1ud2dwNyIsImt1YmVybmV0ZXMuaW8vc2VydmljZWFjY291bnQvc2VydmljZS1hY2NvdW50L
m5hbWUiOiJhZG1pbiIsImt1YmVybmV0ZXMuaW8vc2VydmljZWFjY291bnQvc2VydmljZS1hY2NvdW50LnVpZCI6Im
Q3Nzg2NDIzLTU4ODEtNDg2Zi05YmZjLTcwNDg1MzkzNzYzZCIsInN1YiI6InN5c3RlbTpzZXJ2aWNlYWNjb3VudDp
rdWJlLXN5c3RlbTphZG1pbiJ9.k6z8FvGDbTl3WilcIK2iMvl3ilkBKffIrGV3hMuGrdkwZTScg0Fi6EGjZomi0P4
9MO0LnhjgSm3WiwR4JJmKeSrl0dP-Srh_2wiBnqnwbHySj5ZLorGJDouam9jvdT14gH0CV1og0PC-HB-wuV583iQW1fn9u0qfQKd1LBstdskgG-_FGY730zXz3YwXK3nX12_zCJ3LXcO_tQ9DnIG3kvIP_kYYEzvTidbSnRXlQv2qckeKLyd3g788fjDbfw2wwjYsxsFAfzIMIzVeKwdD5FKhPW2tE4EBo_Vr_pOjuoFCJqgwl1PtxMAulKbF-9Y2RIlvPAL9q0K2E_qC8jBt5w
ca.crt:     1025 bytes
namespace:  11 bytes

然后我们把token复制输入到登录页面即可