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docs/ansible.md

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+Ansible variables
+===============
+
+
+Inventory
+-------------
+The inventory is composed of 3 groups: 
+
+* **kube-node** : list of kubernetes nodes where the pods will run.
+* **kube-master** : list of servers where kubernetes master components (apiserver, scheduler, controller) will run. 
+  Note: if you want the server to act both as master and node the server must be defined on both groups _kube-master_ and _kube-node_
+* **etcd**: list of server to compose the etcd server. you should have at least 3 servers for failover purposes.
+
+Below is a complete inventory example: 
+
+```
+## Configure 'ip' variable to bind kubernetes services on a
+## different ip than the default iface
+node1 ansible_ssh_host=95.54.0.12  # ip=10.3.0.1
+node2 ansible_ssh_host=95.54.0.13  # ip=10.3.0.2
+node3 ansible_ssh_host=95.54.0.14  # ip=10.3.0.3
+node4 ansible_ssh_host=95.54.0.15  # ip=10.3.0.4
+node5 ansible_ssh_host=95.54.0.16  # ip=10.3.0.5
+node6 ansible_ssh_host=95.54.0.17  # ip=10.3.0.6
+
+[kube-master]
+node1
+node2
+
+[etcd]
+node1
+node2
+node3
+
+[kube-node]
+node2
+node3
+node4
+node5
+node6
+
+[k8s-cluster:children]
+kube-node
+kube-master
+etcd
+```
+
+Group vars
+--------------
+The main variables to change are located in the directory ```inventory/group_vars/all.yml```.