Kubeadm join在安装Flannel后无法工作

Question

我正在学习如何从here在ubuntu服务器上安装kubernetes多节点集群的教程。我正在安装法兰绒，而不是印花布。我可以看到flannel安装正确，但是我不能从工作节点加入集群。这是我的文件：

来自/etc/ansible/hosts的主机文件

[workernodes]
X.X.X.X(PUBLIC IP) node_name=worker2 node_internal_ip=10.132.0.16
X.X.X.X(PUBLIC IP) node_name=worker3 node_internal_ip=10.132.0.19
[masternodes]
X.X.X.X(PUBLIC IP) node_name=master node_internal_ip=10.132.0.15

这是我的master-playbook.yml

---
- hosts: masternodes
  become: true
  tasks:

  - name: Remove swapfile from /etc/fstab
    mount:
      name: "{{ item }}"
      fstype: swap
      state: absent
    with_items:
      - swap
      - none

  - name: Disable swap
    command: swapoff -a
    when: ansible_swaptotal_mb > 0

  - name: Letting iptables see bridged traffic
    shell: |
      sudo modprobe br_netfilter
      lsmod | grep br_netfilter


  - name: Install packages that allow apt to be used over HTTPS
    apt:
      name: "{{ packages }}"
      state: present
      update_cache: yes
    vars:
      packages:
      - apt-transport-https
      - ca-certificates
      - curl
      - gnupg-agent
      - software-properties-common

  - name: Add an apt signing key for Docker
    apt_key:
      url: https://download.docker.com/linux/ubuntu/gpg
      state: present

  - name: Add apt repository for stable version
    apt_repository:
      repo: deb [arch=amd64] https://download.docker.com/linux/ubuntu xenial stable
      state: present

  - name: Install docker and its dependecies
    apt: 
      name: "{{ packages }}"
      state: present
      update_cache: yes
    vars:
      packages:
      - docker-ce 
      - docker-ce-cli 
      - containerd.io
    notify:
      - docker status

  # Kubelet, kubeadm, kubec
  - name: Add an apt signing key for Kubernetes
    apt_key:
      url: https://packages.cloud.google.com/apt/doc/apt-key.gpg
      state: present

  - name: Adding apt repository for Kubernetes
    apt_repository:
      repo: deb https://apt.kubernetes.io/ kubernetes-xenial main
      state: present
      filename: kubernetes.list

  - name: Install Kubernetes binaries
    apt: 
      name: "{{ packages }}"
      state: present
      update_cache: yes
    vars:
      packages:
        - kubelet
        - kubeadm
        - kubectl

  - name: Configure node ip
    lineinfile:
      path: /etc/default/kubelet
      line: KUBELET_EXTRA_ARGS=--node-ip={{ node_internal_ip }}
      create: yes

  - name: Restart kubelet
    service:
      name: kubelet
      daemon_reload: yes
      state: restarted


  - name: Initialize the Kubernetes cluster using kubeadm
    command: kubeadm init --apiserver-advertise-address="{{ node_internal_ip }}"   --node-name "{{ node_name }}" --pod-network-cidr="{{ pod_network_cidr }}"

  - name: Setup kubeconfig for "{{ user_name }}" user
    command: "{{ item }}"
    with_items:
     - mkdir -p /home/"{{ user_name }}"/.kube
     - cp -i /etc/kubernetes/admin.conf /home/"{{ user_name }}"/.kube/config
     - chown "{{ user_name }}":"{{ user_name }}" /home/"{{ user_name }}"/.kube/config

  - name: Install Flannel pod network
    become: false
    shell: kubectl create -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
    
  - name: Generate join command
    command: kubeadm token create --print-join-command
    register: join_command

  - name: Copy join command to local file
    local_action: copy content="{{ join_command.stdout_lines[0] }}" dest="./join-command"

  handlers:
    - name: docker status
      service: name=docker state=started

这是我的worker-playbook.yml

---
- hosts: workernodes
  become: true
  tasks:

  - name: Remove swapfile from /etc/fstab
    mount:
      name: "{{ item }}"
      fstype: swap
      state: absent
    with_items:
      - swap
      - none

  - name: Disable swap
    command: swapoff -a
    when: ansible_swaptotal_mb > 0

  - name: Letting iptables see bridged traffic
    shell: |
      sudo modprobe br_netfilter
      lsmod | grep br_netfilter


  - name: Install packages that allow apt to be used over HTTPS
    apt:
      name: "{{ packages }}"
      state: present
      update_cache: yes
    vars:
      packages:
      - apt-transport-https
      - ca-certificates
      - curl
      - gnupg-agent
      - software-properties-common

  - name: Add an apt signing key for Docker
    apt_key:
      url: https://download.docker.com/linux/ubuntu/gpg
      state: present

  - name: Add apt repository for stable version
    apt_repository:
      repo: deb [arch=amd64] https://download.docker.com/linux/ubuntu xenial stable
      state: present

  - name: Install docker and its dependecies
    apt: 
      name: "{{ packages }}"
      state: present
      update_cache: yes
    vars:
      packages:
      - docker-ce 
      - docker-ce-cli 
      - containerd.io
    notify:
      - docker status

  - name: Add an apt signing key for Kubernetes
    apt_key:
      url: https://packages.cloud.google.com/apt/doc/apt-key.gpg
      state: present

  - name: Adding apt repository for Kubernetes
    apt_repository:
      repo: deb https://apt.kubernetes.io/ kubernetes-xenial main
      state: present
      filename: kubernetes.list

  - name: Install Kubernetes binaries
    apt: 
      name: "{{ packages }}"
      state: present
      update_cache: yes
    vars:
      packages:
        - kubelet 
        - kubeadm
        - kubectl

  - name: Configure node ip
    lineinfile:
      path: /etc/default/kubelet
      line: KUBELET_EXTRA_ARGS=--node-ip={{ node_internal_ip }}
      create: yes

  - name: Restart kubelet
    service:
      name: kubelet
      daemon_reload: yes
      state: restarted

  - name: Copy the join command to server location
    copy: src=join-command dest=/tmp/join-command.sh mode=0777

  - name: Join the node to cluster
    shell: |
      echo " --node-name {{ node_name }}" >> /tmp/join-command.sh 
      sh /tmp/join-command.sh

  handlers:
    - name: docker status
      service: name=docker state=started

我也在使用pod_network_cidr="10.132.0.0/20。当我第一次运行master-playbook，然后运行worker-playbook时，worker节点卡在join part中。

以下是kubectl get pods --all-namespaces日志：

kube-system   coredns-558bd4d5db-mlw6r                             1/1     Running   0          2m3s
kube-system   coredns-558bd4d5db-r4ptb                             1/1     Running   0          2m4s
kube-system   etcd.master-0                                        1/1     Running   0          2m18s
kube-system   kube-apiserver.master-0                              1/1     Running   0          2m18s
kube-system   kube-controller-manager.master-0                     1/1     Running   0          2m21s
kube-system   kube-flannel-ds-tvvdl                                1/1     Running   0          2m4s
kube-system   kube-proxy-pwb7h                                     1/1     Running   0          2m4s
kube-system   kube-schedulerr-0                                    1/1     Running   0          2m18s

但是在worker-node中尝试join命令之后，我得到了这个错误：

Failed to request cluster-info, will try again: Get "https://10.132.0.15:6443/api/v1/namespaces/kube-public/configmaps/cluster-info?timeout=10s": net/http: re
quest canceled while waiting for connection (Client.Timeout exceeded while awaiting headers)

防火墙已正确打开，但我无法从工作节点ping主节点。

你能帮帮我吗？

Answer 1

根据documentation，您应该记住Pod网络不能与任何主机网络重叠:如果有任何重叠，您可能会看到问题。此外，考虑到您使用的是Flannel而不是Calico，请记住，它们似乎在.yaml文件中指定了不同的CIDR范围- 10.244.0.0/16 for Flannel和192.168.0.0/16 for Calico，并且.yaml文件中的CIDR范围应该与您在安装过程中指定的CIDR范围相匹配。