在k8s中安装flannel的故障解决： Failed to create SubnetManager: error retrieving pod spec for : the server does not allow access to the requested resource

花了一个上午来追踪问题，k8s都反复新建了十多次，docker都重启了几次。(一次显示不有获取磁盘空间，重启docker，清空存储解决)

在用kubeadm安装容器化的几个组件时，flannel组件死活不能启动，报如下问题：

Failed to create SubnetManager: error retrieving pod spec for 'kube-system/kube-flannel-ds-xxx': the server does not allow access to the requested resource.

在如下Url找到解决办法：

http://blog.csdn.net/ximenghappy/article/details/70157361

明天搞DNS和节点加入....

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Kubernetes一共提供五种网络组件，可以根据自己的需要选择。我使用的Flannel网络，此处1.5.5和1.6.1也是不一样的，1.6.1加了RBAC。需要执行一下两个命令：

kubectl create -f https://github.com/coreos/flannel/raw/master/Documentation/kube-flannel-rbac.yml
clusterrole "flannel" configured
clusterrolebinding "flannel" configured

kubectl create -f  https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
serviceaccount "flannel" created
configmap "kube-flannel-cfg" created
daemonset "kube-flannel-ds" created

　　解决此问题参考： 
https://github.com/kubernetes/kubernetes/issues/44029 
https://github.com/kubernetes/kubeadm/issues/212#issuecomment-290908868

kube-flannel-rbac.yaml文件内容:

# Create the clusterrole and clusterrolebinding:
# $ kubectl create -f kube-flannel-rbac.yml
# Create the pod using the same namespace used by the flannel serviceaccount:
# $ kubectl create --namespace kube-system -f kube-flannel.yml
---
kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1beta1
metadata:
  name: flannel
rules:
  - apiGroups:
      - ""
    resources:
      - pods
    verbs:
      - get
  - apiGroups:
      - ""
    resources:
      - nodes
    verbs:
      - list
      - watch
  - apiGroups:
      - ""
    resources:
      - nodes/status
    verbs:
      - patch
---
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1beta1
metadata:
  name: flannel
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: flannel
subjects:
- kind: ServiceAccount
  name: flannel
  namespace: kube-system

kube-flannel.yaml内容:

---
apiVersion: v1
kind: ServiceAccount
metadata:
  name: flannel
  namespace: kube-system
---
kind: ConfigMap
apiVersion: v1
metadata:
  name: kube-flannel-cfg
  namespace: kube-system
  labels:
    tier: node
    app: flannel
data:
  cni-conf.json: |
    {
      "name": "cbr0",
      "type": "flannel",
      "delegate": {
        "isDefaultGateway": true
      }
    }
  net-conf.json: |
    {
      "Network": "10.244.0.0/16",
      "Backend": {
        "Type": "vxlan"
      }
    }
---
apiVersion: extensions/v1beta1
kind: DaemonSet
metadata:
  name: kube-flannel-ds
  namespace: kube-system
  labels:
    tier: node
    app: flannel
spec:
  template:
    metadata:
      labels:
        tier: node
        app: flannel
    spec:
      hostNetwork: true
      nodeSelector:
        beta.kubernetes.io/arch: amd64
      tolerations:
      - key: node-role.kubernetes.io/master
        operator: Exists
        effect: NoSchedule
      serviceAccountName: flannel
      containers:
      - name: kube-flannel
        image: quay.io/coreos/flannel-amd64:v0.7.1
        command: [ "/opt/bin/flanneld", "--ip-masq", "--kube-subnet-mgr" ]
        securityContext:
          privileged: true
        env:
        - name: POD_NAME
          valueFrom:
            fieldRef:
              fieldPath: metadata.name
        - name: POD_NAMESPACE
          valueFrom:
            fieldRef:
              fieldPath: metadata.namespace
        volumeMounts:
        - name: run
          mountPath: /run
        - name: flannel-cfg
          mountPath: /etc/kube-flannel/
      - name: install-cni
        image: quay.io/coreos/flannel-amd64:v0.7.1
        command: [ "/bin/sh", "-c", "set -e -x; cp -f /etc/kube-flannel/cni-conf.json /etc/cni/net.d/10-flannel.conf; while true; do sleep 3600; done" ]
        volumeMounts:
        - name: cni
          mountPath: /etc/cni/net.d
        - name: flannel-cfg
          mountPath: /etc/kube-flannel/
      volumes:
        - name: run
          hostPath:
            path: /run
        - name: cni
          hostPath:
            path: /etc/cni/net.d
        - name: flannel-cfg
          configMap:
            name: kube-flannel-cfg