The documentation for installing kubectl, kubeadm, and kubelet is like a combination of riddle and maze (always forget where the link is). So I wrote this.
Install these with 🌟Ansible:
- docker
- containerd
- kubeadm v1.28
- kubectl
- kubelet
$ ansible-playbook playbook-k8s-configure.yml -i <wherever you're ansible inventory is> --diff
# main.yml
- name: Load overlay and br_netfilter
include_tasks: loadKernelModule.yml
loop:
- overlay
- br_netfilter
- name: sysctl params required by setup, params persist across reboots
become: true
lineinfile:
path: /etc/sysctl.d/k8s.conf
state: present
create: true
line: "{{ item }}"
loop:
- "net.bridge.bridge-nf-call-iptables = 1"
- "net.bridge.bridge-nf-call-ip6tables = 1"
- "net.ipv4.ip_forward = 1"
- name: Apply sysctl params without reboot
become: true
shell: sysctl --system
# main.yml
- name: Verify that br_netfilter is loaded
shell: lsmod | grep br_netfilter
changed_when: false
ignore_errors: true
register: out_betfilter
- name: Fail if br_netfilter is not loaded
fail:
msg: "br_netfilter is not loaded"
when: out_betfilter.rc != 0
- name: Verify that overlay is loaded
shell: lsmod | grep overlay
changed_when: false
ignore_errors: true
register: out_overlay
- name: Fail if overlay is not loaded
fail:
msg: "overlay is not loaded"
when: out_overlay.rc != 0
3. Verify net.bridge.bridge-nf-call-iptables, net.bridge.bridge-nf-call-ip6tables, and net.ipv4.ip_forward system variables
# main.yml
- name: Verify sysctl
become: true
shell: sudo sysctl net.bridge.bridge-nf-call-iptables net.bridge.bridge-nf-call-ip6tables net.ipv4.ip_forward
changed_when: false
register: out_sysctl
- name: Fail if system variables are not set to 1
fail:
msg: "system variable {{ item }} does not end with 1"
when: item.split("=")[-1].strip() != "1"
with_items: "{{ out_sysctl.stdout_lines }}"
Speed-up by checking if docker has been installed. Do no install docker if it's already in the machine.
# installContainerd_Ubuntu.yml
- name: Check if Docker is installed
command: "docker --version"
ignore_errors: true
register: docker_check
- name: Install Docker and containerd
block:
- name: ...
- name: ...
...
become: true
when: docker_check.rc != 0
Install containerd based on the OS you're using: https://github.com/containerd/containerd/blob/main/docs/getting-started.md#option-2-from-apt-get-or-dnf. This repo only works for Ubuntu and Debian.
For Ubuntu: https://docs.docker.com/engine/install/ubuntu/#install-using-the-repository
# installContainerd_Ubuntu.yml
- name: Install Docker and containerd
block:
- name: apt-get update
...
- name: Create directory /etc/apt/keyrings
...
- name: Check if the Docker GPG key file exists
...
- name: Fetch the Docker GPG key and save the dearmored key
...
- name: Change the permmision of dearmored key
...
- name: Get version codename
...
- name: Get arch
...
- name: Print codename and arch
...
- name: Add repository to Apt sources
...
- name: Test add repository
become: true
register: config_changed
...
Update the apt package and install Docker and containerd
https://docs.docker.com/engine/install/ubuntu/#install-using-the-repository
# installContainerd_Ubuntu.yml
- name: Install Docker and containerd
block:
...
- name: Run apt-get update and install docker packages
apt:
update_cache: true
name:
- docker-ce
- docker-ce-cli
- containerd.io
- docker-buildx-plugin
- docker-compose-plugin
become: true
register: config_changed
# installContainerd_Ubuntu.yml
- name: Set /etc/containerd/config.toml
ansible.builtin.blockinfile:
path: /etc/containerd/config.toml
block: |
[plugins."io.containerd.grpc.v1.cri".containerd.runtimes.runc]
[plugins."io.containerd.grpc.v1.cri".containerd.runtimes.runc.options]
SystemdCgroup = true
become: true
register: config_changed
- name: Restart containerd
ansible.builtin.systemd:
name: containerd
state: restarted
become: true
when: config_changed is changed
https://v1-28.docs.kubernetes.io/docs/setup/production-environment/tools/kubeadm/install-kubeadm/#check-required-ports This step is not in the playbook yet :(
# installKubeadm_Debian.yml
- name: Install packages needed to use the Kubernetes apt repository
apt:
update_cache: true
name:
- apt-transport-https
- ca-certificates
- curl
- gpg
become: true
- name: Check if the kubernetes signing key file exists
stat:
path: /etc/apt/keyrings/kubernetes-apt-keyring.gpg
register: k8s_gpg_key_check
- name: Download the public signing key for the Kubernetes package repositories
shell: curl -fsSL https://pkgs.k8s.io/core:/stable:/v1.28/deb/Release.key | sudo gpg --dearmor -o /etc/apt/keyrings/kubernetes-apt-keyring.gpg
when: not k8s_gpg_key_check.stat.exists
- name: Add repository for kubernetes 1.28 to Apt sources
ansible.builtin.lineinfile:
path: /etc/apt/sources.list.d/kubernetes.list
line: "deb [signed-by=/etc/apt/keyrings/kubernetes-apt-keyring.gpg] https://pkgs.k8s.io/core:/stable:/v1.28/deb/ /"
state: present
create: yes
become: true
# installKubeadm_Debian.yml
- name: Install packages needed to use the Kubernetes apt repository
apt:
update_cache: true
name:
- kubelet
- kubeadm
- kubectl
become: true
- name: Prevent kubernetes being upgraded
shell: apt-mark hold kubelet kubeadm kubectl
become: true