r/keepalived: Deploy keepalived

[keepalived][0] is a free implementation of the Virtual Router
Redundancy Protocol (VRRP), which is a simple method for automatically
assigning an IP address to one of several potential hosts based on
certain criteria.  It is particularly useful in conjunction with a load
balancer like HAProxy, to provide layer 3 redundancy in addition to
layer 7.  We will use it for both the reverse proxy for the public
websites and the Kubernetes API server.

[0]: https://www.keepalived.org/

roles/keepalived/handlers/main.yml

@@ -0,0 +1,4 @@
+- name: reload keepalived
+  service:
+    name: keepalived
+    state: reloaded

roles/keepalived/tasks/main.yml

@@ -0,0 +1,34 @@
+- name: ensure keepalived is installed
+  package:
+    name: keepalived
+    state: present
+  tags:
+  - install
+
+- name: ensure keepalived is configured
+  template:
+    src: keepalived.conf.j2
+    dest: /etc/keepalived/keepalived.conf
+    owner: root
+    group: root
+    mode: u=rw,go=r
+  notify: reload keepalived
+  tags:
+  - config
+
+- name: flush handlers
+  meta: flush_handlers
+
+- name: ensure keepalived starts at boot
+  service:
+    name: keepalived
+    enabled: true
+  tags:
+  - service
+
+- name: ensure keepalived is running
+  service:
+    name: keepalived
+    state: started
+  tags:
+  - service

roles/keepalived/templates/keepalived.conf.j2

@@ -0,0 +1,24 @@
+{#- vim: set sw=3 sts=3 ts=3 et : -#}
+! Configuration File for keepalived
+{% if keepalived_global_defs|d %}
+
+global_defs {
+{{ keepalived_global_defs | indent(width=3, first=true) }}
+}
+{% endif %}
+{% if vrrp_track_process|d %}
+
+{% for name, config in vrrp_track_process | items %}
+vrrp_track_process {{ name }} {
+{{ config | indent(width=4, first=true) }}
+}
+{% endfor %}
+{% endif %}
+{% if vrrp_instance|d %}
+
+{% for name, config in vrrp_instance | items %}
+vrrp_instance {{ name }} {
+{{ config | indent(width=4, first=true) }}
+}
+{% endfor %}
+{% endif %}