写一个ansible的playbook自动化部署一个三master二node的k8s集群

好的，以下是一个简单的Ansible Playbook，可以自动化部署一个三master二node的Kubernetes集群。

1. 首先，我们需要创建一个inventory文件，指定服务器的IP地址和SSH用户名。在本例中，我们将使用`hosts.ini`文件：

[masters]
192.168.1.1
192.168.1.2
192.168.1.3

[nodes]
192.168.1.4
192.168.1.5

[all:vars]
ansible_user=ubuntu

2. 接下来，我们需要创建一个`deploy-k8s.yml`文件，定义Kubernetes集群的部署步骤：

---
- hosts: all
  become: yes

  tasks:
    - name: Install Docker
      apt:
        name:
          - docker.io
          - apt-transport-https
          - ca-certificates
          - curl
          - gnupg-agent
          - software-properties-common
        state: present

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

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

    - name: Install Kubernetes components
      apt:
        name:
          - kubelet
          - kubeadm
          - kubectl
        state: present

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

    - name: Initialize Kubernetes cluster
      command: kubeadm init --control-plane-endpoint "loadbalancer" --upload-certs --pod-network-cidr=10.244.0.0/16
      become: yes
      args:
        creates: /etc/kubernetes/admin.conf

    - name: Copy Kubernetes config file to user's home directory
      copy:
        src: /etc/kubernetes/admin.conf
        dest: /home/{{ ansible_user }}/admin.conf
        owner: "{{ ansible_user }}"

    - name: Create Kubernetes directory for user
      file:
        path: /home/{{ ansible_user }}/.kube
        state: directory
        owner: "{{ ansible_user }}"

    - name: Copy Kubernetes config file to user's .kube directory
      copy:
        src: /etc/kubernetes/admin.conf
        dest: /home/{{ ansible_user }}/.kube/config
        owner: "{{ ansible_user }}"

    - name: Install Flannel CNI plugin
      command: kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
      become: yes
      args:
        creates: /etc/kubernetes/cni/net.d/10-flannel.conflist

    - name: Join worker nodes to Kubernetes cluster
      command: kubeadm join loadbalancer:6443 --token <token> --discovery-token-ca-cert-hash <hash>
      become: yes
      when: inventory_hostname in groups['nodes']

    - name: Copy Kubernetes config file to worker nodes
      copy:
        src: /etc/kubernetes/admin.conf
        dest: /tmp/admin.conf

    - name: Set Kubernetes config file for worker nodes
      command: kubectl config --kubeconfig=/tmp/admin.conf use-context kubernetes-admin@kubernetes
      become: yes
      when: inventory_hostname in groups['nodes']

3. 最后，我们可以运行这个Playbook来自动化部署Kubernetes集群：

ansible-playbook -i hosts.ini deploy-k8s.yml

这个Playbook将会在所有服务器上安装Docker和Kubernetes组件，禁用swap，初始化Kubernetes集群，安装Flannel CNI插件，将节点加入到集群中，并且在工作节点上设置Kubernetes配置文件。