Ansible部署K8s集群
目录
- 检查网络：k8s-check.yaml
- 连接配置：k8s-conn-cfg.yaml
- 配置k8s集群dns解析： k8s-hosts-cfg.yaml
- 配置yum源：k8s-yum-cfg.yaml
- 时钟同步：k8s-time-sync.yaml
- 禁用iptable、firewalld、NetworkManager服务
- 禁用SElinux、swap：k8s-SE-swap-disable.yaml
- 修改内核：k8s-kernel-cfg.yaml
- 配置ipvs：k8s-ipvs-cfg.yaml
- 安装docker：k8s-docker-install.yaml
- 安装k8s组件[kubeadm\kubelet\kubectl]：k8s-install-kubepkgs.yaml
- 安装集群镜像：k8s-apps-images.yaml
- k8s集群初始化：k8s-cluster-init.yaml
环境：
| 主机 | IP地址 | 组件 |
|---|---|---|
| ansible | 192.168.175.130 | ansible |
| master | 192.168.175.140 | docker，kubectl，kubeadm，kubelet |
| node | 192.168.175.141 | docker，kubectl，kubeadm，kubelet |
| node | 192.168.175.142 | docker，kubectl，kubeadm，kubelet |
检查及调试相关命令：
$ ansible-playbook -v k8s-time-sync.yaml --syntax-check
$ ansible-playbook -v k8s-*.yaml -C
$ ansible-playbook -v k8s-yum-cfg.yaml -C --start-at-task="Clean origin dir" --step
$ ansible-playbook -v k8s-kernel-cfg.yaml --step
主机inventory文件：
/root/ansible/hosts
[k8s_cluster]
master ansible_host=192.168.175.140
node1 ansible_host=192.168.175.141
node2 ansible_host=192.168.175.142
[k8s_cluster:vars]
ansible_port=22
ansible_user=root
ansible_password=hello123
检查网络：k8s-check.yaml
- 检查
k8s各主机的网络是否可达; - 检查
k8s各主机操作系统版本是否达到要求；
- name: step01_check
hosts: k8s_cluster
gather_facts: no
tasks:
- name: check network
shell:
cmd: "ping -c 3 -m 2 {{ansible_host}}"
delegate_to: localhost
- name: get system version
shell: cat /etc/system-release
register: system_release
- name: check system version
vars:
system_version: "{{ system_release.stdout | regex_search('([7-9].[0-9]+).*?') }}"
suitable_version: 7.5
debug:
msg: "{{ 'The version of the operating system is '+ system_version +', suitable!' if (system_version | float >= suitable_version) else 'The version of the operating system is unsuitable' }}"
调试命令：
$ ansible-playbook --ssh-extra-args '-o StrictHostKeyChecking=no' -v -C k8s-check.yaml
$ ANSIBLE_HOST_KEY_CHECKING=False ansible-playbook -v -C k8s-check.yaml
$ ANSIBLE_HOST_KEY_CHECKING=False ansible-playbook -v k8s-check.yaml --start-at-task="get system version"
连接配置：k8s-conn-cfg.yaml
- 在
ansible服务器的/etc/hosts文件中添加k8s主机名解析配置 - 生成密钥对，配置
ansible免密登录到k8s各主机
- name: step02_conn_cfg
hosts: k8s_cluster
gather_facts: no
vars_prompt:
- name: RSA
prompt: Generate RSA or not(Yes/No)?
default: "no"
private: no
- name: password
prompt: input your login password?
default: "hello123"
tasks:
- name: Add DNS of k8s to ansible
delegate_to: localhost
lineinfile:
path: /etc/hosts
line: "{{ansible_host}} {{inventory_hostname}}"
backup: yes
- name: Generate RSA
run_once: true
delegate_to: localhost
shell:
cmd: ssh-keygen -t rsa -f ~/.ssh/id_rsa -N ''
creates: /root/.ssh/id_rsa
when: RSA | bool
- name: Configure password free login
delegate_to: localhost
shell: |
/usr/bin/ssh-keyscan {{ ansible_host }} >> /root/.ssh/known_hosts 2> /dev/null
/usr/bin/ssh-keyscan {{ inventory_hostname }} >> /root/.ssh/known_hosts 2> /dev/null
/usr/bin/sshpass -p'{{ password }}' ssh-copy-id root@{{ ansible_host }}
#/usr/bin/sshpass -p'{{ password }}' ssh-copy-id root@{{ inventory_hostname }}
- name: Test ssh
shell: hostname
执行：
$ ansible-playbook k8s-conn-cfg.yaml
Generate RSA or not(Yes/No)? [no]: yes
input your login password? [hello123]:
PLAY [step02_conn_cfg] **********************************************************************************************************
TASK [Add DNS of k8s to ansible] ************************************************************************************************
ok: [master -> localhost]
ok: [node1 -> localhost]
ok: [node2 -> localhost]
TASK [Generate RSA] *************************************************************************************************************
changed: [master -> localhost]
TASK [Configure password free login] ********************************************************************************************
changed: [node1 -> localhost]
changed: [master -> localhost]
changed: [node2 -> localhost]
TASK [Test ssh] *****************************************************************************************************************
changed: [master]
changed: [node1]
changed: [node2]
PLAY RECAP **********************************************************************************************************************
master : ok=4 changed=3 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0
node1 : ok=3 changed=2 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0
node2 : ok=3 changed=2 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0
配置k8s集群dns解析： k8s-hosts-cfg.yaml
- 设置主机名
/etc/hosts文件中互相添加dns解析
- name: step03_cfg_host
hosts: k8s_cluster
gather_facts: no
tasks:
- name: set hostname
hostname:
name: "{{ inventory_hostname }}"
use: systemd
- name: Add dns to each other
lineinfile:
path: /etc/hosts
backup: yes
line: "{{item.value.ansible_host}} {{item.key}}"
loop: "{{ hostvars | dict2items }}"
loop_control:
label: "{{ item.key }} {{ item.value.ansible_host }}"
执行：
$ ansible-playbook k8s-hosts-cfg.yaml
PLAY [step03_cfg_host] **********************************************************************************************************
TASK [set hostname] *************************************************************************************************************
ok: [master]
ok: [node1]
ok: [node2]
TASK [Add dns to each other] ****************************************************************************************************
ok: [node2] => (item=node1 192.168.175.141)
ok: [master] => (item=node1 192.168.175.141)
ok: [node1] => (item=node1 192.168.175.141)
ok: [node2] => (item=node2 192.168.175.142)
ok: [master] => (item=node2 192.168.175.142)
ok: [node1] => (item=node2 192.168.175.142)
ok: [node2] => (item=master 192.168.175.140)
ok: [master] => (item=master 192.168.175.140)
ok: [node1] => (item=master 192.168.175.140)
PLAY RECAP **********************************************************************************************************************
master : ok=2 changed=0 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0
node1 : ok=2 changed=0 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0
node2 : ok=2 changed=0 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0
配置yum源：k8s-yum-cfg.yaml
- name: step04_yum_cfg
hosts: k8s_cluster
gather_facts: no
tasks:
- name: Create back-up directory
file:
path: /etc/yum.repos.d/org/
state: directory
- name: Back-up old Yum files
shell:
cmd: mv -f /etc/yum.repos.d/*.repo /etc/yum.repos.d/org/
removes: /etc/yum.repos.d/org/
- name: Add new Yum files
copy:
src: ./files_yum/
dest: /etc/yum.repos.d/
- name: Check yum.repos.d
shell:
cmd: ls /etc/yum.repos.d/*
时钟同步：k8s-time-sync.yaml
- name: step05_time_sync
hosts: k8s_cluster
gather_facts: no
tasks:
- name: Start chronyd.service
systemd:
name: chronyd.service
state: started
enabled: yes
- name: Modify time zone & clock
shell: |
cp -f /usr/share/zoneinfo/Asia/Shanghai /etc/localtime
clock -w
hwclock -w
- name: Check time now
command: date
禁用iptable、firewalld、NetworkManager服务
- name: step06_net_service
hosts: k8s_cluster
gather_facts: no
tasks:
- name: Stop some services for net
systemd:
name: "{{ item }}"
state: stopped
enabled: no
loop:
- firewalld
- iptables
- NetworkManager
执行：
$ ansible-playbook -v k8s-net-service.yaml
... ...
failed: [master] (item=iptables) => {
"ansible_loop_var": "item",
"changed": false,
"item": "iptables"
}
MSG:
Could not find the requested service iptables: host
... ...
PLAY RECAP **********************************************************************************************************************
master : ok=0 changed=0 unreachable=0 failed=1 skipped=0 rescued=0 ignored=0
node1 : ok=0 changed=0 unreachable=0 failed=1 skipped=0 rescued=0 ignored=0
node2 : ok=0 changed=0 unreachable=0 failed=1 skipped=0 rescued=0 ignored=0
禁用SElinux、swap：k8s-SE-swap-disable.yaml
- name: step07_net_service
hosts: k8s_cluster
gather_facts: no
tasks:
- name: SElinux disabled
lineinfile:
path: /etc/selinux/config
line: SELINUX=disabled
regexp: ^SELINUX=
state: present
backup: yes
- name: Swap disabled
lineinfile:
path: /etc/fstab
line: '#\1'
regexp: '(^/dev/mapper/centos-swap.*$)'
backrefs: yes
state: present
backup: yes
修改内核：k8s-kernel-cfg.yaml
- name: step08_kernel_cfg
hosts: k8s_cluster
gather_facts: no
tasks:
- name: Create /etc/sysctl.d/kubernetes.conf
copy:
content: ''
dest: /etc/sysctl.d/kubernetes.conf
force: yes
- name: Cfg bridge and ip_forward
lineinfile:
path: /etc/sysctl.d/kubernetes.conf
line: "{{ item }}"
state: present
loop:
- 'net.bridge.bridge-nf-call-ip6tables = 1'
- 'net.bridge.bridge-nf-call-iptables = 1'
- 'net.ipv4.ip_forward = 1'
- name: Load cfg
shell:
cmd: |
sysctl -p
modprobe br_netfilter
removes: /etc/sysctl.d/kubernetes.conf
- name: Check cfg
shell:
cmd: '[ $(lsmod | grep br_netfilter | wc -l) -ge 2 ] && exit 0 || exit 3'
执行：
$ ansible-playbook -v k8s-kernel-cfg.yaml --step
TASK [Check cfg] ****************************************************************************************************************
changed: [master] => {
"changed": true,
"cmd": "[ $(lsmod | grep br_netfilter | wc -l) -ge 2 ] && exit 0 || exit 3",
"delta": "0:00:00.011574",
"end": "2022-02-27 04:26:01.332896",
"rc": 0,
"start": "2022-02-27 04:26:01.321322"
}
changed: [node2] => {
"changed": true,
"cmd": "[ $(lsmod | grep br_netfilter | wc -l) -ge 2 ] && exit 0 || exit 3",
"delta": "0:00:00.016331",
"end": "2022-02-27 04:26:01.351208",
"rc": 0,
"start": "2022-02-27 04:26:01.334877"
}
changed: [node1] => {
"changed": true,
"cmd": "[ $(lsmod | grep br_netfilter | wc -l) -ge 2 ] && exit 0 || exit 3",
"delta": "0:00:00.016923",
"end": "2022-02-27 04:26:01.355983",
"rc": 0,
"start": "2022-02-27 04:26:01.339060"
}
PLAY RECAP **********************************************************************************************************************
master : ok=4 changed=4 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0
node1 : ok=4 changed=4 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0
node2 : ok=4 changed=4 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0
配置ipvs：k8s-ipvs-cfg.yaml
- name: step09_ipvs_cfg
hosts: k8s_cluster
gather_facts: no
tasks:
- name: Install ipset and ipvsadm
yum:
name: "{{ item }}"
state: present
loop:
- ipset
- ipvsadm
- name: Load modules
shell: |
modprobe -- ip_vs
modprobe -- ip_vs_rr
modprobe -- ip_vs_wrr
modprobe -- ip_vs_sh
modprobe -- nf_conntrack_ipv4
- name: Check cfg
shell:
cmd: '[ $(lsmod | grep -e -ip_vs -e nf_conntrack_ipv4 | wc -l) -ge 2 ] && exit 0 || exit 3'
安装docker：k8s-docker-install.yaml
- name: step10_docker_install
hosts: k8s_cluster
gather_facts: no
tasks:
- name: Install docker-ce
yum:
name: docker-ce-18.06.3.ce-3.el7
state: present
- name: Cfg docker
copy:
src: ./files_docker/daemon.json
dest: /etc/docker/
- name: Start docker
systemd:
name: docker.service
state: started
enabled: yes
- name: Check docker version
shell:
cmd: docker --version
安装k8s组件[kubeadm\kubelet\kubectl]：k8s-install-kubepkgs.yaml
- name: step11_k8s_install_kubepkgs
hosts: k8s_cluster
gather_facts: no
tasks:
- name: Install k8s components
yum:
name: "{{ item }}"
state: present
loop:
- kubeadm-1.17.4-0
- kubelet-1.17.4-0
- kubectl-1.17.4-0
- name: Cfg k8s
copy:
src: ./files_k8s/kubelet
dest: /etc/sysconfig/
force: no
backup: yes
- name: Start kubelet
systemd:
name: kubelet.service
state: started
enabled: yes
安装集群镜像：k8s-apps-images.yaml
- name: step12_apps_images
hosts: k8s_cluster
gather_facts: no
vars:
apps:
- kube-apiserver:v1.17.4
- kube-controller-manager:v1.17.4
- kube-scheduler:v1.17.4
- kube-proxy:v1.17.4
- pause:3.1
- etcd:3.4.3-0
- coredns:1.6.5
vars_prompt:
- name: cfg_python
prompt: Do you need to install docker pkg for python(Yes/No)?
default: "no"
private: no
tasks:
- block:
- name: Install python-pip
yum:
name: python-pip
state: present
- name: Install docker pkg for python
shell:
cmd: |
pip install docker==4.4.4
pip install websocket-client==0.32.0
creates: /usr/lib/python2.7/site-packages/docker/
when: cfg_python | bool
- name: Pull images
community.docker.docker_image:
name: "registry.cn-hangzhou.aliyuncs.com/google_containers/{{ item }}"
source: pull
loop: "{{ apps }}"
- name: Tag images
community.docker.docker_image:
name: "registry.cn-hangzhou.aliyuncs.com/google_containers/{{ item }}"
repository: "k8s.gcr.io/{{ item }}"
force_tag: yes
source: local
loop: "{{ apps }}"
- name: Remove images for ali
community.docker.docker_image:
name: "registry.cn-hangzhou.aliyuncs.com/google_containers/{{ item }}"
state: absent
loop: "{{ apps }}"
执行：
$ ansible-playbook k8s-apps-images.yaml
Do you need to install docker pkg for python(Yes/No)? [no]:
PLAY [step12_apps_images] *******************************************************************************************************
TASK [Install python-pip] *******************************************************************************************************
skipping: [node1]
skipping: [master]
skipping: [node2]
TASK [Install docker pkg for python] ********************************************************************************************
skipping: [master]
skipping: [node1]
skipping: [node2]
TASK [Pull images] **************************************************************************************************************
changed: [node1] => (item=kube-apiserver:v1.17.4)
changed: [node2] => (item=kube-apiserver:v1.17.4)
changed: [master] => (item=kube-apiserver:v1.17.4)
changed: [node1] => (item=kube-controller-manager:v1.17.4)
changed: [master] => (item=kube-controller-manager:v1.17.4)
changed: [node1] => (item=kube-scheduler:v1.17.4)
changed: [master] => (item=kube-scheduler:v1.17.4)
changed: [node1] => (item=kube-proxy:v1.17.4)
changed: [node2] => (item=kube-controller-manager:v1.17.4)
changed: [master] => (item=kube-proxy:v1.17.4)
changed: [node1] => (item=pause:3.1)
changed: [master] => (item=pause:3.1)
changed: [node2] => (item=kube-scheduler:v1.17.4)
changed: [node1] => (item=etcd:3.4.3-0)
changed: [master] => (item=etcd:3.4.3-0)
changed: [node2] => (item=kube-proxy:v1.17.4)
changed: [node1] => (item=coredns:1.6.5)
changed: [master] => (item=coredns:1.6.5)
changed: [node2] => (item=pause:3.1)
changed: [node2] => (item=etcd:3.4.3-0)
changed: [node2] => (item=coredns:1.6.5)
TASK [Tag images] ***************************************************************************************************************
ok: [node1] => (item=kube-apiserver:v1.17.4)
ok: [master] => (item=kube-apiserver:v1.17.4)
ok: [node2] => (item=kube-apiserver:v1.17.4)
ok: [node1] => (item=kube-controller-manager:v1.17.4)
ok: [master] => (item=kube-controller-manager:v1.17.4)
ok: [node2] => (item=kube-controller-manager:v1.17.4)
ok: [master] => (item=kube-scheduler:v1.17.4)
ok: [node1] => (item=kube-scheduler:v1.17.4)
ok: [node2] => (item=kube-scheduler:v1.17.4)
ok: [master] => (item=kube-proxy:v1.17.4)
ok: [node1] => (item=kube-proxy:v1.17.4)
ok: [node2] => (item=kube-proxy:v1.17.4)
ok: [master] => (item=pause:3.1)
ok: [node1] => (item=pause:3.1)
ok: [node2] => (item=pause:3.1)
ok: [master] => (item=etcd:3.4.3-0)
ok: [node1] => (item=etcd:3.4.3-0)
ok: [node2] => (item=etcd:3.4.3-0)
ok: [master] => (item=coredns:1.6.5)
ok: [node1] => (item=coredns:1.6.5)
ok: [node2] => (item=coredns:1.6.5)
TASK [Remove images for ali] ****************************************************************************************************
changed: [master] => (item=kube-apiserver:v1.17.4)
changed: [node2] => (item=kube-apiserver:v1.17.4)
changed: [node1] => (item=kube-apiserver:v1.17.4)
changed: [master] => (item=kube-controller-manager:v1.17.4)
changed: [node1] => (item=kube-controller-manager:v1.17.4)
changed: [node2] => (item=kube-controller-manager:v1.17.4)
changed: [node1] => (item=kube-scheduler:v1.17.4)
changed: [master] => (item=kube-scheduler:v1.17.4)
changed: [node2] => (item=kube-scheduler:v1.17.4)
changed: [master] => (item=kube-proxy:v1.17.4)
changed: [node1] => (item=kube-proxy:v1.17.4)
changed: [node2] => (item=kube-proxy:v1.17.4)
changed: [node1] => (item=pause:3.1)
changed: [master] => (item=pause:3.1)
changed: [node2] => (item=pause:3.1)
changed: [master] => (item=etcd:3.4.3-0)
changed: [node1] => (item=etcd:3.4.3-0)
changed: [node2] => (item=etcd:3.4.3-0)
changed: [master] => (item=coredns:1.6.5)
changed: [node1] => (item=coredns:1.6.5)
changed: [node2] => (item=coredns:1.6.5)
PLAY RECAP **********************************************************************************************************************
master : ok=3 changed=2 unreachable=0 failed=0 skipped=2 rescued=0 ignored=0
node1 : ok=3 changed=2 unreachable=0 failed=0 skipped=2 rescued=0 ignored=0
node2 : ok=3 changed=2 unreachable=0 failed=0 skipped=2 rescued=0 ignored=0
k8s集群初始化：k8s-cluster-init.yaml
- name: step13_cluster_init
hosts: master
gather_facts: no
tasks:
- block:
- name: Kubeadm init
shell:
cmd:
kubeadm init
--apiserver-advertise-address={{ ansible_host }}
--kubernetes-version=v1.17.4
--service-cidr=10.96.0.0/12
--pod-network-cidr=10.244.0.0/16
--image-repository registry.aliyuncs.com/google_containers
- name: Create /root/.kube
file:
path: /root/.kube/
state: directory
owner: root
group: root
- name: Copy /root/.kube/config
copy:
src: /etc/kubernetes/admin.conf
dest: /root/.kube/config
remote_src: yes
backup: yes
owner: root
group: root
- name: Copy kube-flannel
copy:
src: ./files_k8s/kube-flannel.yml
dest: /root/
backup: yes
- name: Apply kube-flannel
shell:
cmd: kubectl apply -f /root/kube-flannel.yml
- name: Get token
shell:
cmd: kubeadm token create --print-join-command
register: join_token
- name: debug join_token
debug:
var: join_token.stdout
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