refactored kubernetes playbook

1 files changed, 101 insertions, 0 deletions

diff --git a/common/kubernetes.yml b/common/kubernetes.yml
new file mode 100644
index 00000000..1ad583af
--- /dev/null
+++ b/common/kubernetes.yml
@@ -0,0 +1,101 @@
+---
+- name: prepare variables and do some sanity checks
+  hosts: _kubernetes_nodes_
+  gather_facts: no
+  run_once: yes
+  tasks:
+  - name: check if master group contains only one node
+    fail:
+      msg: "There must be exactly one master node defined"
+    failed_when: (groups['_kubernetes_masters_'] | length) != 1
+
+  - name: setup variables
+    set_fact:
+      kubernetes_nodes: "{{ groups['_kubernetes_nodes_'] }}"
+      kubernetes_master: "{{ groups['_kubernetes_masters_'] | first }}"
+
+  - name: check whether every node has a net_index assigned
+    fail:
+      msg: "There are nodes without an assigned net-index: {{ kubernetes_nodes | difference(kubernetes.net_index.keys()) | join(', ') }}"
+    failed_when: kubernetes_nodes | difference(kubernetes.net_index.keys()) | length > 0
+
+  - name: check whether net indizes are unique
+    fail:
+      msg: "There are duplicate entries in the net_index table, every net-index is only allowed once"
+    failed_when: (kubernetes.net_index.keys() | length) != (kubernetes.net_index.values() | unique | length)
+
+  - name: check whether net indizes are all > 0
+    fail:
+      msg: "At least one net-index is < 1 (indizes start at 1)"
+    failed_when: (kubernetes.net_index.values() | min) < 1
+
+########
+- name: install kubernetes and overlay network
+  hosts: _kubernetes_nodes_
+  roles:
+  ## Since `base` has a dependency for docker it would install and start the daemon
+  ## without the docker daemon config file generated by `net`.
+  ## This means that the docker daemon will create a bridge and install iptables rules
+  ## upon first startup (the first time this playbook runs on a specific host).
+  ## Since it is a tedious task to remove the interface and the firewall rules it is much
+  ## easier to just run `net` before `base` as `net` does not need anything from `base`.
+  - role: kubernetes/net
+  - role: kubernetes/base
+
+- name: configure kubernetes master
+  hosts: _kubernetes_masters_
+  roles:
+  - role: kubernetes/master
+
+- name: configure kubernetes non-master nodes
+  hosts: _kubernetes_nodes_:!_kubernetes_masters_
+  roles:
+  - role: kubernetes/node
+
+########
+- name: check for nodes to be removed
+  hosts: _kubernetes_masters_
+  tasks:
+  - name: fetch list of current nodes
+    command: kubectl get nodes -o name
+    changed_when: False
+    check_mode: no
+    register: kubectl_node_list
+
+  - name: generate list of nodes to be removed
+    with_items: "{{ kubectl_node_list.stdout_lines | map('replace', 'nodes/', '') | list | difference(kubernetes_nodes) }}"
+    add_host:
+      name: "{{ item }}"
+      inventory_dir: "{{ inventory_dir }}"
+      group: _kubernetes_nodes_remove_
+    changed_when: False
+
+  - name: drain superflous nodes
+    with_items: "{{ groups['_kubernetes_nodes_remove_'] | default([]) }}"
+    command: "kubectl drain {{ item }} --delete-local-data --force --ignore-daemonsets"
+
+- name: try to clean superflous nodes
+  hosts: _kubernetes_nodes_remove_
+  vars:
+    kubernetes_remove_node: yes
+  roles:
+  - role: kubernetes/node
+  - role: kubernetes/net
+
+- name: remove node from api server
+  hosts: _kubernetes_masters_
+  tasks:
+  - name: remove superflous nodes
+    with_items: "{{ groups['_kubernetes_nodes_remove_'] | default([]) }}"
+    command: "kubectl delete node {{ item }}"
+
+  - name: wait a litte before removing bootstrap-token so new nodes have time to generate certificates for themselves
+    when: kube_bootstrap_token != ""
+    pause:
+      seconds: 42
+
+  - name: remove bootstrap-token
+    when: kube_bootstrap_token != ""
+    command: "kubectl --namespace kube-system delete secret bootstrap-token-{{ kube_bootstrap_token.split('.') | first }}"
+
+### TODO: add node labels (ie. for ingress daeomnset)