kubernetes: new/updated kubeadm master role (WIP)

1 files changed, 120 insertions, 0 deletions

diff --git a/roles/kubernetes/kubeadm/master/tasks/primary-master.yml b/roles/kubernetes/kubeadm/master/tasks/primary-master.yml
new file mode 100644
index 00000000..58658794
--- /dev/null
+++ b/roles/kubernetes/kubeadm/master/tasks/primary-master.yml
@@ -0,0 +1,120 @@
+---
+- name: check if kubeconfig kubelet.conf already exists
+  stat:
+    path: /etc/kubernetes/kubelet.conf
+  register: kubeconfig_kubelet_stats
+
+- name: generate kubeadm.config
+  template:
+    src: kubeadm.config.j2
+    dest: /etc/kubernetes/kubeadm.config
+  register: kubeadm_config
+
+### cluster not yet initialized
+
+- name: create new cluster
+  when: not kubeconfig_kubelet_stats.stat.exists
+  block:
+
+  #### kubeadm wants token to come from --config if --config is used
+  #### i think this is stupid -> TODO: send bug report
+  # - name: generate bootstrap token for new cluster
+  #   command: kubeadm token generate
+  #   changed_when: False
+  #   check_mode: no
+  #   register: kubeadm_token_generate
+
+  - name: initialize kubernetes master
+    command: "kubeadm init --config /etc/kubernetes/kubeadm.config{% if kubernetes_cri_socket is defined %} --cri-socket {{ kubernetes_cri_socket }}{% endif %}{% if kubernetes_network_plugin == 'kube-router' %} --skip-phases addon/kube-proxy{% endif %} --skip-token-print"
+#    command: "kubeadm init --config /etc/kubernetes/kubeadm.config{% if kubernetes_cri_socket is defined %} --cri-socket {{ kubernetes_cri_socket }}{% endif %}{% if kubernetes_network_plugin == 'kube-router' %} --skip-phases addon/kube-proxy{% endif %} --token '{{ kubeadm_token_generate.stdout }}' --token-ttl 42m --skip-token-print"
+    args:
+      creates: /etc/kubernetes/pki/ca.crt
+    register: kubeadm_init
+
+  - name: dump output of kubeadm init to log file
+    when: kubeadm_init.changed
+    copy:
+      content: "{{ kubeadm_init.stdout }}\n"
+      dest: /etc/kubernetes/kubeadm-init.log
+
+  - name: create bootstrap token for existing cluster
+    command: kubeadm token create --ttl 42m
+    check_mode: no
+    register: kubeadm_token_generate
+
+### cluster is already initialized but config has changed
+
+- name: upgrade cluster config
+  when: kubeconfig_kubelet_stats.stat.exists and kubeadm_config is changed
+  block:
+
+
+  - name: fail for cluster upgrades
+    fail:
+      msg: "upgrading cluster config is currently not supported!"
+
+
+### cluster is already initialized
+
+- name: prepare cluster for new nodes
+  when: kubeconfig_kubelet_stats.stat.exists and kubeadm_config is not changed
+  block:
+
+  - name: fetch list of current nodes
+    command: kubectl --kubeconfig /etc/kubernetes/admin.conf get nodes -o name
+    changed_when: False
+    check_mode: no
+    register: kubectl_node_list
+
+  - name: save list of current nodes
+    set_fact:
+      kubernetes_current_nodes: "{{ kubectl_node_list.stdout_lines | map('replace', 'node/', '') | list }}"
+
+  - name: create bootstrap token for existing cluster
+    when: "groups['_kubernetes_nodes_'] | map('extract', hostvars) | map(attribute='host_name') | difference(kubernetes_current_nodes) | length > 0"
+    command: kubeadm token create --ttl 42m
+    check_mode: no
+    register: kubeadm_token_create
+
+##
+
+## this fixes the kubelet kubeconfig to make use of certificate rotation. This is a bug in
+## kubeadm init which was fixed with 1.17 release. TODO: remove this once all cluster have been
+## upgraded to 1.17 or newer.
+- name: fix kubeconfig of kubelet
+  lineinfile:
+    path: /etc/kubernetes/kubelet.conf
+    backrefs: yes
+    regexp: '^(\s*)client-{{ item }}(-data)?:'
+    line: '\1client-{{ item }}: /var/lib/kubelet/pki/kubelet-client-current.pem'
+  with_items:
+    - certificate
+    - key
+  notify: restart kubelet
+
+
+- name: install openssl
+  apt:
+    name: openssl
+    state: present
+
+- name: get ca certificate digest
+  shell: "set -o pipefail && openssl x509 -pubkey -in /etc/kubernetes/pki/ca.crt | openssl rsa -pubin -outform der 2>/dev/null | openssl dgst -sha256 -hex | sed 's/^.* //'"
+  args:
+    executable: /bin/bash
+  check_mode: no
+  register: kube_ca_openssl
+  changed_when: False
+
+- name: set variables needed by kubernetes/nodes to join the cluster
+  set_fact:
+    kube_bootstrap_token: "{% if kubeadm_token_generate.stdout is defined %}{{ kubeadm_token_generate.stdout }}{% elif kubeadm_token_create.stdout is defined %}{{ kubeadm_token_create.stdout }}{% endif %}"
+    kube_bootstrap_ca_cert_hash: "sha256:{{ kube_ca_openssl.stdout }}"
+  delegate_to: "{{ item }}"
+  delegate_facts: True
+  loop: "{{ groups['_kubernetes_nodes_'] }}"
+
+## Network Plugin
+
+# - name: install network plugin
+#   include_tasks: "net_{{ kubernetes_network_plugin }}.yml"