Este artigo propõe automatizar a instalação do Kubernetes 1.13 no Raspberry Pi via Ansible com um papel caseiro.

Pré-requisitos

Instalação do Docker + Kubernetes

Recuperação do papel
Eu desenvolvi um papel ansible para esta automatização, veja como recuperá-lo:

## Pré-requis Docker (rôle fait maison)
git clone https://gitlab.com/jls42/ansible-rpi-docker.git roles/ansible-rpi-docker
## Rôle pour l'installation de Kubernetes
git clone https://gitlab.com/jls42/ansible-rpi-k8s.git roles/ansible-rpi-k8s

Para mais detalhes veja a documentação em ansible-rpi-k8s

Criação do arquivo de inventário chamado inventory
Neste exemplo de inventário, há vários Raspberry Pi 1, um possui o IP 192.168.1.190 e o outro o IP 192.168.1.191
No grupo filho (aqui rpi-k8s), o master deve ser declarado primeiro

[rpi1]
192.168.1.190 k8s_master=true

[rpi2]
192.168.1.191

[rpi-k8s:children]
rpi1
rpi2

Preparação do playbook k8s-rpi.yml

---
- name: "Installation de Docker sur le Raspberry Pi"
  hosts: rpi-k8s
  remote_user: "pi"
  roles:
    - roles/ansible-rpi-docker
  vars:
    docker_version: 18.06.1~ce~3-0~raspbian

- name: "Installation de k8s sur le Raspberry Pi"
  hosts: rpi-k8s
  remote_user: "pi"
  roles:
    - roles/ansible-rpi-k8s
  vars:
    k8s_version: "1.13.0-00"
    k8s_master_token: "abcdef.0123456789abcdef"
    k8s_cluster_group: rpi-k8s

Implantação do Docker e Kubernetes
Os papéis ansible-rpi-docker e ansible-rpi-k8s serão executados em sequência.
No caso do docker já estar instalado, é possível executar apenas ansible-rpi-k8s.

export ANSIBLE_HOST_KEY_CHECKING=False
ansible-playbook -b -i inventory k8s-rpi.yml

O que resulta em:

jls42@boo:~/rpi$ ansible-playbook -b -i inventory k8s-rpi.yml

PLAY [Installation de Docker sur le Raspberry Pi] ******************************************************************************************************************************************************************************************

TASK [Gathering Facts] *********************************************************************************************************************************************************************************************************************
Sunday 09 December 2018  03:26:30 +0100 (0:00:00.051)       0:00:00.051 *******
ok: [192.168.1.190]
ok: [192.168.1.191]

TASK [roles/ansible-rpi-docker : Installe les paquets nécessaire à l'utilisation d'un dépôt HTTPS] *****************************************************************************************************************************************
Sunday 09 December 2018  03:26:33 +0100 (0:00:03.476)       0:00:03.527 *******
changed: [192.168.1.190] => (item=[u'apt-transport-https', u'ca-certificates', u'curl', u'gnupg2', u'software-properties-common'])
changed: [192.168.1.191] => (item=[u'apt-transport-https', u'ca-certificates', u'curl', u'gnupg2', u'software-properties-common'])

TASK [roles/ansible-rpi-docker : Ajoute la clef officielle du dépôt Docker] ****************************************************************************************************************************************************************
Sunday 09 December 2018  03:27:12 +0100 (0:00:39.274)       0:00:42.802 *******
changed: [192.168.1.190]
changed: [192.168.1.191]

TASK [roles/ansible-rpi-docker : Ajoute le dépôt Docker] ***********************************************************************************************************************************************************************************
Sunday 09 December 2018  03:27:17 +0100 (0:00:04.747)       0:00:47.549 *******
changed: [192.168.1.190]
changed: [192.168.1.191]

TASK [roles/ansible-rpi-docker : Installe le paquet docker-ce] *****************************************************************************************************************************************************************************
Sunday 09 December 2018  03:27:27 +0100 (0:00:10.238)       0:00:57.788 *******
changed: [192.168.1.190]
changed: [192.168.1.191]

TASK [roles/ansible-rpi-docker : Installe python-pip] **************************************************************************************************************************************************************************************
Sunday 09 December 2018  03:29:04 +0100 (0:01:36.285)       0:02:34.074 *******
changed: [192.168.1.191]
changed: [192.168.1.190]

TASK [roles/ansible-rpi-docker : Installe docker-compose via pip] **************************************************************************************************************************************************************************
Sunday 09 December 2018  03:30:06 +0100 (0:01:02.641)       0:03:36.715 *******
changed: [192.168.1.191]
changed: [192.168.1.190]

TASK [roles/ansible-rpi-docker : Configure Docker pour qu'il démarre au boot] **************************************************************************************************************************************************************
Sunday 09 December 2018  03:31:03 +0100 (0:00:56.384)       0:04:33.099 *******
ok: [192.168.1.190]
ok: [192.168.1.191]

TASK [roles/ansible-rpi-docker : Ajoute l'utilisateur pi dans le groupe docker] ************************************************************************************************************************************************************
Sunday 09 December 2018  03:31:04 +0100 (0:00:01.075)       0:04:34.175 *******
changed: [192.168.1.191]
changed: [192.168.1.190]

TASK [roles/ansible-rpi-docker : Supprime la swap] *****************************************************************************************************************************************************************************************
Sunday 09 December 2018  03:31:05 +0100 (0:00:01.348)       0:04:35.523 *******
changed: [192.168.1.190]
changed: [192.168.1.191]
PLAY [Installation de k8s sur le Raspberry Pi] *********************************************************************************************************************************************************************************************

TASK [Gathering Facts] *********************************************************************************************************************************************************************************************************************
Sunday 09 December 2018  03:31:07 +0100 (0:00:02.096)       0:04:37.620 *******
ok: [192.168.1.190]
ok: [192.168.1.191]

TASK [roles/ansible-rpi-k8s : Installe les paquets nécessaires à l'utilisation d'un dépôt HTTPS] *******************************************************************************************************************************************
Sunday 09 December 2018  03:31:09 +0100 (0:00:01.934)       0:04:39.555 *******
ok: [192.168.1.190] => (item=[u'apt-transport-https', u'ca-certificates', u'curl', u'gnupg2', u'software-properties-common'])
ok: [192.168.1.191] => (item=[u'apt-transport-https', u'ca-certificates', u'curl', u'gnupg2', u'software-properties-common'])

TASK [roles/ansible-rpi-k8s : Supprime la swap] ********************************************************************************************************************************************************************************************
Sunday 09 December 2018  03:31:15 +0100 (0:00:05.740)       0:04:45.295 *******
ok: [192.168.1.190]
ok: [192.168.1.191]

TASK [roles/ansible-rpi-k8s : Active cgroup_memory] ****************************************************************************************************************************************************************************************
Sunday 09 December 2018  03:31:16 +0100 (0:00:00.966)       0:04:46.262 *******
changed: [192.168.1.190]
changed: [192.168.1.191]

TASK [roles/ansible-rpi-k8s : Redémarre] ***************************************************************************************************************************************************************************************************
Sunday 09 December 2018  03:31:17 +0100 (0:00:01.032)       0:04:47.295 *******
changed: [192.168.1.191]
changed: [192.168.1.190]

TASK [roles/ansible-rpi-k8s : Attente suite au redémarrage] ********************************************************************************************************************************************************************************
Sunday 09 December 2018  03:31:18 +0100 (0:00:01.667)       0:04:48.962 *******
ok: [192.168.1.190]
ok: [192.168.1.191]

TASK [roles/ansible-rpi-k8s : Ajoute la clef officielle Kubernetes] ************************************************************************************************************************************************************************
Sunday 09 December 2018  03:32:19 +0100 (0:01:00.447)       0:05:49.409 *******
changed: [192.168.1.190]
changed: [192.168.1.191]

TASK [roles/ansible-rpi-k8s : Ajoute le dépôt stable de Kubernetes] ************************************************************************************************************************************************************************
Sunday 09 December 2018  03:32:25 +0100 (0:00:06.282)       0:05:55.692 *******
changed: [192.168.1.190]
changed: [192.168.1.191]

TASK [roles/ansible-rpi-k8s : Installe kubeadm, kubelet and kubectl] ***********************************************************************************************************************************************************************
Sunday 09 December 2018  03:32:45 +0100 (0:00:20.277)       0:06:15.970 *******
changed: [192.168.1.190] => (item=[u'kubeadm=1.13.0-00', u'kubelet=1.13.0-00', u'kubectl=1.13.0-00'])
changed: [192.168.1.191] => (item=[u'kubeadm=1.13.0-00', u'kubelet=1.13.0-00', u'kubectl=1.13.0-00'])

TASK [roles/ansible-rpi-k8s : Configure kubelet pour qu'il démarre au boot] ****************************************************************************************************************************************************************
Sunday 09 December 2018  03:34:25 +0100 (0:01:39.895)       0:07:55.865 *******
ok: [192.168.1.191]
ok: [192.168.1.190]

TASK [roles/ansible-rpi-k8s : Installe les paquets nécessaires pour l'utilisation du client CIFS] ******************************************************************************************************************************************
Sunday 09 December 2018  03:34:26 +0100 (0:00:01.029)       0:07:56.894 *******
changed: [192.168.1.191] => (item=[u'cifs-utils', u'util-linux', u'coreutils', u'jq'])
changed: [192.168.1.190] => (item=[u'cifs-utils', u'util-linux', u'coreutils', u'jq'])

TASK [roles/ansible-rpi-k8s : Ajout le répertoire d'addons cifs] ***************************************************************************************************************************************************************************
Sunday 09 December 2018  03:34:40 +0100 (0:00:13.835)       0:08:10.730 *******
changed: [192.168.1.191]
changed: [192.168.1.190]

TASK [roles/ansible-rpi-k8s : Télécharge le plugin CIFS] ***********************************************************************************************************************************************************************************
Sunday 09 December 2018  03:34:41 +0100 (0:00:01.051)       0:08:11.782 *******
changed: [192.168.1.191]
changed: [192.168.1.190]
TASK [roles/ansible-rpi-k8s : Installe les paquets nécessaires à l'utilisation du client GlusterFS] *********************************************************************************************************************************************************
Sunday 09 December 2018  03:34:43 +0100 (0:00:01.740)       0:08:13.522 *******
changed: [192.168.1.190] => (item=[u'glusterfs-client'])
changed: [192.168.1.191] => (item=[u'glusterfs-client'])

TASK [roles/ansible-rpi-k8s : Définie l'ip du maître] **************************************************************************************************************************************************************************************
Sunday 09 December 2018  03:35:16 +0100 (0:00:32.640)       0:08:46.162 *******
ok: [192.168.1.190]
ok: [192.168.1.191]

TASK [roles/ansible-rpi-k8s : Vérifie si le master a déjà été configuré] *******************************************************************************************************************************************************************
Sunday 09 December 2018  03:35:16 +0100 (0:00:00.113)       0:08:46.276 *******
skipping: [192.168.1.191]
ok: [192.168.1.190]

TASK [roles/ansible-rpi-k8s : Définie l'initialisation du cluster à oui] *******************************************************************************************************************************************************************
Sunday 09 December 2018  03:35:17 +0100 (0:00:01.074)       0:08:47.350 *******
skipping: [192.168.1.191]
ok: [192.168.1.190]

TASK [roles/ansible-rpi-k8s : Définie l'initialisation du cluster à non] *******************************************************************************************************************************************************************
Sunday 09 December 2018  03:35:17 +0100 (0:00:00.113)       0:08:47.464 *******
skipping: [192.168.1.190]
skipping: [192.168.1.191]

TASK [roles/ansible-rpi-k8s : Définie l'initialisation du/des noeud(s)] ********************************************************************************************************************************************************************
Sunday 09 December 2018  03:35:17 +0100 (0:00:00.097)       0:08:47.562 *******
skipping: [192.168.1.190]
ok: [192.168.1.191]

TASK [roles/ansible-rpi-k8s : Initialise le cluster Kubernetes sur le maître] **************************************************************************************************************************************************************
Sunday 09 December 2018  03:35:17 +0100 (0:00:00.181)       0:08:47.743 *******
skipping: [192.168.1.191]
changed: [192.168.1.190]

TASK [roles/ansible-rpi-k8s : Attend la fin de l'initialisation] ***************************************************************************************************************************************************************************
Sunday 09 December 2018  03:35:19 +0100 (0:00:01.598)       0:08:49.342 *******
skipping: [192.168.1.191]
FAILED - RETRYING: Attend la fin de l'initialisation (42 retries left).
FAILED - RETRYING: Attend la fin de l'initialisation (41 retries left).
FAILED - RETRYING: Attend la fin de l'initialisation (40 retries left).
FAILED - RETRYING: Attend la fin de l'initialisation (39 retries left).
FAILED - RETRYING: Attend la fin de l'initialisation (38 retries left).
FAILED - RETRYING: Attend la fin de l'initialisation (37 retries left).
FAILED - RETRYING: Attend la fin de l'initialisation (36 retries left).
FAILED - RETRYING: Attend la fin de l'initialisation (35 retries left).
FAILED - RETRYING: Attend la fin de l'initialisation (34 retries left).
FAILED - RETRYING: Attend la fin de l'initialisation (33 retries left).
FAILED - RETRYING: Attend la fin de l'initialisation (32 retries left).
changed: [192.168.1.190]

TASK [roles/ansible-rpi-k8s : Crée le répertoire kubernetes /home/pi/.kube/] ***************************************************************************************************************************************************************
Sunday 09 December 2018  03:41:02 +0100 (0:05:43.339)       0:14:32.682 *******
skipping: [192.168.1.191]
changed: [192.168.1.190]

TASK [roles/ansible-rpi-k8s : Copie le fichier /etc/kubernetes/admin.conf vers /home/pi/.kube/config] **************************************************************************************************************************************
Sunday 09 December 2018  03:41:03 +0100 (0:00:00.948)       0:14:33.630 *******
skipping: [192.168.1.191]
changed: [192.168.1.190]

TASK [roles/ansible-rpi-k8s : Récupère la configuration kubernetes dans un répertoire local] ***********************************************************************************************************************************************
Sunday 09 December 2018  03:41:04 +0100 (0:00:01.030)       0:14:34.661 *******
skipping: [192.168.1.191]
changed: [192.168.1.190]
TASK [roles/ansible-rpi-k8s : Jointure de(s) noeud(s) avec le maître] **********************************************************************************************************************************************************************
Sunday 09 December 2018  03:41:05 +0100 (0:00:01.016)       0:14:35.678 *******
skipping: [192.168.1.190]
changed: [192.168.1.191]

TASK [roles/ansible-rpi-k8s : Installation des pods réseaux avec Weave] ********************************************************************************************************************************************************************
Sunday 09 December 2018  03:41:12 +0100 (0:00:06.567)       0:14:42.245 *******
skipping: [192.168.1.191]
changed: [192.168.1.190]

PLAY RECAP *********************************************************************************************************************************************************************************************************************************
192.168.1.190              : ok=33   changed=23   unreachable=0    failed=0   
192.168.1.191              : ok=27   changed=18   unreachable=0    failed=0   

Sunday 09 December 2018  03:41:18 +0100 (0:00:05.893)       0:14:48.139 *******
===============================================================================
roles/ansible-rpi-k8s ------------------------------------------------- 608.58s
roles/ansible-rpi-docker ---------------------------------------------- 274.09s
setup ------------------------------------------------------------------- 5.41s
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
total ----------------------------------------------------------------- 888.09s
Playbook run took 0 days, 0 hours, 14 minutes, 48 seconds

Verificação

Conecte-se ao Raspberry Pi para confirmar a boa instalação do Kubernetes
(os nós não estarão necessariamente todos em estado “Ready” imediatamente, isso pode levar alguns minutos)

jls42@boo:~/rpi$ ssh pi@192.168.1.190
Linux rpi1 4.14.79-v7+ #1159 SMP Sun Nov 4 17:50:20 GMT 2018 armv7l

The programs included with the Debian GNU/Linux system are free software;
the exact distribution terms for each program are described in the
individual files in /usr/share/doc/*/copyright.

Debian GNU/Linux comes with ABSOLUTELY NO WARRANTY, to the extent
permitted by applicable law.
Last login: Sun Dec  9 02:41:12 2018 from 192.168.1.42
pi@rpi1:~ $ kubectl get nodes -o wide
NAME   STATUS   ROLES    AGE    VERSION   INTERNAL-IP     EXTERNAL-IP   OS-IMAGE                         KERNEL-VERSION   CONTAINER-RUNTIME
rpi1   Ready    master   2m3s   v1.13.0   192.168.1.190   <none>        Raspbian GNU/Linux 9 (stretch)   4.14.79-v7+      docker://18.6.1
rpi2   Ready    <none>   85s    v1.13.0   192.168.1.191   <none>        Raspbian GNU/Linux 9 (stretch)   4.14.79-v7+      docker://18.6.1
pi@rpi1:~ $

E sabendo que a configuração k8s foi copiada localmente, também é possível executar kubectl no computador local (se este estiver instalado).

Enjoy!

Este documento foi traduzido da versão fr para a língua pt utilizando o modelo gpt-4o. Para mais informações sobre o processo de tradução, consulte https://gitlab.com/jls42/ai-powered-markdown-translator.