Test live migration with config drive

Tempest live migration tests do not create the server
with config drive so we do not, by default, have test
coverage of live migrating an instance with a config
drive. This change forces nova to create a config
drive for all instances in the nova-live-migration
job which will also run evacuate tests with a config
drive attached.

Change-Id: I8157b9e6e9da492a225cbb50a20f434f83a5fecb
Related-Bug: #1770640

.zuul.yaml

@@ -118,6 +118,7 @@
       Run tempest live migration tests against both local storage and shared
       storage using ceph (the environment is reconfigured for ceph after the
       local storage tests are run). Also runs simple evacuate tests.
+      Config drive is forced on all instances.
     run: playbooks/legacy/nova-live-migration/run.yaml
     post-run: playbooks/legacy/nova-live-migration/post.yaml
 

playbooks/legacy/nova-live-migration/run.yaml

@@ -23,6 +23,21 @@
         chdir: '{{ ansible_user_dir }}/workspace'
       environment: '{{ zuul | zuul_legacy_vars }}'
 
+    - name: Configure devstack
+      shell:
+        # Force config drive.
+        cmd: |
+          set -e
+          set -x
+          cat << 'EOF' >>"/tmp/dg-local.conf"
+          [[local|localrc]]
+          FORCE_CONFIG_DRIVE=True
+
+          EOF
+        executable: /bin/bash
+        chdir: '{{ ansible_user_dir }}/workspace'
+      environment: '{{ zuul | zuul_legacy_vars }}'
+
     - shell:
         cmd: |
           set -e