Split deployment and teardown playbooks

Create deploy.yml and teardown.yml which mostly run the same playbooks in
opposite orders. Also document the new structure.

README.md

@@ -54,14 +54,20 @@ are:
 
 ### Running Tenks
 
-Currently, Tenks does not have a CLI or wrapper. It can be run by calling
-`ansible-playbook --inventory ansible/inventory ansible/run.yml --extra-vars=@override.yml`,
-where `override.yml` is the path to your override file. The `run.yml` playbook
-includes various constituent playbooks which perform different parts of the
-deployment. An individual section of Tenks can be run separately by
-substituting `ansible/run.yml` in the command above with the path to the
-playbook you want to run. The current playbooks can be seen in the Ansible
-structure diagram in the *Development* section.
+Currently, Tenks does not have a CLI or wrapper. Deployment can be run by
+calling `ansible-playbook --inventory ansible/inventory ansible/deploy.yml
+--extra-vars=@override.yml`, where `override.yml` is the path to your override
+file.
+
+The `deploy.yml` playbook will run deployment from start to finish;
+`teardown.yml` is `deploy.yml`'s "mirror image" to tear down a cluster. These
+playbooks automatically set `cmd` appropriately, and they contain various
+constituent playbooks which perform different parts of the deployment. An
+individual section of Tenks can be run separately by substituting
+`ansible/deploy.yml` in the command above with the path to the playbook(s) you
+want to run. The current playbooks can be seen in the Ansible structure diagram
+in the *Development* section. Bear in mind that you will have to set `cmd` in
+your override file if you are running any of the sub-playbooks individually.
 
 ## Development
 

ansible/deploy.yml

@@ -1,10 +1,15 @@
 ---
-- name: Perform deployment host configuration
-  import_playbook: host_setup.yml
+- hosts: all
+  tasks:
+    - set_fact:
+        cmd: deploy
 
 - name: Schedule nodes
   import_playbook: schedule.yml
 
+- name: Perform deployment host configuration
+  import_playbook: host_setup.yml
+
 - name: Configure node networking
   import_playbook: node_networking.yml
 

ansible/teardown.yml

@@ -0,0 +1,26 @@
+---
+- hosts: all
+  tasks:
+    - set_fact:
+        cmd: teardown
+
+- name: Schedule removal of nodes
+  import_playbook: schedule.yml
+
+- name: Deregister flavors in Nova
+  import_playbook: flavor_registration.yml
+
+- name: Perform Ironic node deconfiguration
+  import_playbook: node_enrolment.yml
+
+- name: Deconfigure virtual node BMCs
+  import_playbook: node_bmc.yml
+
+- name: De-instantiate nodes
+  import_playbook: node_instantiation.yml
+
+- name: Deconfigure node networking
+  import_playbook: node_networking.yml
+
+- name: Perform deployment host deconfiguration
+  import_playbook: host_setup.yml