Workaround missing etcd certds on control plane node (#12193)

Co-authored-by: Max Gautier <mg@max.gautier.name>

roles/etcd/tasks/gen_certs_script.yml

@@ -98,6 +98,28 @@
   loop_control:
     label: "{{ item.item }}"
 
+# This is a hack around the fact kubeadm expect the same certs path on all kube_control_plane
+# TODO: fix certs generation to have the same file everywhere
+# OR work with kubeadm on node-specific config
+- name: Gen_certs | Pretend all control plane have all certs (with symlinks)
+  file:
+    state: link
+    src: "{{ etcd_cert_dir }}/node-{{ inventory_hostname }}{{ item[0] }}.pem"
+    dest: "{{ etcd_cert_dir }}/node-{{ item[1] }}{{ item[0] }}.pem"
+    mode: "0640"
+  loop: "{{ suffixes | product(groups['kube_control_plane']) }}"
+  vars:
+    suffixes:
+      - ''
+      - '-key'
+  when:
+    - ('kube_control_plane' in group_names)
+    - item[1] != inventory_hostname
+  register: symlink_created
+  failed_when:
+    - symlink_created is failed
+    - ('refusing to convert from file to symlink' not in symlink_created.msg)
+
 - name: Gen_certs | Gather node certs from first etcd node
   slurp:
     src: "{{ item }}"