Fix nova-lxd tests for bionic.

This patch adjusts the nova-lxd deployment so that it works correctly
with LXD3 and bionic.

* Update the zuul job and project config to switch from xenial to bionic.

* Change the variable lxd_storage_pool to always have a defined value
  in the role defaults. This variable represents the name of the LXD
  storage pool which is distinct from any names associated with underlying
  storage. LXD storage pools created with 'lxd init' are always called 'default'.

* Switch the role test storage backend from dir to ZFS. nova-lxd is
  currently not working for the dir backend as it expects the storage
  subsystem to support quotas.

* Due to limitiations in nova-lxd it is necessary to ensure that the
  LXD storage pool name and ZFS pool names are both set to 'default'.

Closes-Bug: #1800837
Change-Id: If1e48bb2e789e13f20435da19907b5adb7c1ef1f

defaults/main.yml

@@ -632,9 +632,13 @@ lxd_storage_backend: dir
 # This needs to be set in the user_secrets.yml file.
 #lxd_trust_password:
 
-# This variable should be used with lxd when using a
-# storage backend that utilizes storage pools (zfs)
-#lxd_storage_pool:
+# The name of the underlying storage pool created by, or consumed by
+# lxd init. As an example this would be the name of a ZFS pool.
+#lxd_init_storage_pool: pool
+
+# Nova requires the LXD storage pool name to be specified
+lxd_storage_pool: default
+
 # This variable should be used with lxd when using a
 # storage backend that utilizes storage pool if you
 # want to use a specific bloc device instead of loop

releasenotes/notes/default-lxd-pool-1aa179bd77868cb0.yaml

@@ -0,0 +1,11 @@
+---
+features:
+  - |
+    The nova configuration is updated to always specify an LXD storage pool
+    name when 'nova_virt_type' is 'lxd'. The variable 'lxd_storage_pool' is
+    defaulted to 'default', the LXD default storage pool name. A new variable
+    'lxd_init_storage_pool' is introduced which specifies the underlying
+    storage pool name. 'lxd_init_storage_pool' is used by lxd init when setting
+    up the storage pool. If not provided, lxd init will not use this parameter
+    at all. Please see the lxd man page for further information about the
+    storage pool parameter.

templates/lxd-init.sh.j2

@@ -11,8 +11,8 @@
   --network-address={{ lxd_bind_address }} \
   --network-port={{ lxd_bind_port }} \
   --storage-backend={{ lxd_storage_backend }} \
-{% if lxd_storage_pool is defined %}
-  --storage-pool={{ lxd_storage_pool }} \
+{% if lxd_init_storage_pool is defined %}
+  --storage-pool={{ lxd_init_storage_pool }} \
 {% endif %}
 {% if lxd_storage_create_device is defined %}
   --storage-create-device={{ lxd_storage_create_device }} \
@@ -29,4 +29,3 @@ if [ $(findmnt /var/lib/lxd -o FSTYPE -n) == "btrfs" ]; then
 fi
 
 {% endif %}
-

templates/nova.conf.j2

@@ -280,7 +280,7 @@ hw_disk_discard = {{ nova_libvirt_hw_disk_discard }}
 disk_cachemodes = {{ nova_libvirt_disk_cachemodes }}
 {% endif %}
 
-{% if nova_virt_type == 'lxd' and lxd_storage_pool is defined %}
+{% if nova_virt_type == 'lxd' %}
 [lxd]
 pool= {{ lxd_storage_pool }}
 {% endif %}

tests/os_nova-overrides-lxd.yml

@@ -14,6 +14,8 @@
 # limitations under the License.
 
 nova_virt_type: lxd
+lxd_storage_backend: zfs
+lxd_init_storage_pool: default
 
 tempest_test_whitelist:
   - tempest.scenario.test_server_basic_ops.TestServerBasicOps.test_server_basic_ops

tests/test-create-zfs-dev.yml

@@ -0,0 +1,48 @@
+---
+# Copyright 2018, BBC R&D
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+- name: Configure ZFS backing storage
+  hosts: localhost
+  user: root
+  become: true
+  connection: local
+  tasks:
+    - block:
+      - name: Install ZFS packages
+        package:
+          name: "{{ zfs_package[ansible_distribution | lower] }}"
+          state: present
+
+      - name: Create base directories
+        file:
+          path: "{{ item }}"
+          state: "directory"
+        with_items:
+          - /openstack
+
+      - name: Create sparse ZFS backing file
+        command: "truncate -s 1024G /openstack/nova-lxd-zfs.img"
+        args:
+          creates: /openstack/nova-lxd-zfs.img
+        register: lxc_zfs_create
+
+      - name: Create the ZFS pool
+        command: zpool create default /openstack/nova-lxd-zfs.img
+        args:
+          creates: /default
+
+  vars:
+    zfs_package:
+      ubuntu: "zfsutils-linux"

tests/test.yml

@@ -13,6 +13,11 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+# Setup ZFS pool for nova-lxd tests
+- import_playbook: test-create-zfs-dev.yml
+  when:
+    - nova_virt_type is defined and nova_virt_type == "lxd"
+
 # Setup the host
 - import_playbook: common/test-setup-host.yml
 

zuul.d/jobs.yaml

@@ -14,7 +14,7 @@
 # limitations under the License.
 
 - job:
-    name: openstack-ansible-lxd-ubuntu-xenial
-    parent: openstack-ansible-functional-ubuntu-xenial
+    name: openstack-ansible-lxd-ubuntu-bionic
+    parent: openstack-ansible-functional-ubuntu-bionic
     vars:
       tox_env: lxd

zuul.d/project.yaml

@@ -21,7 +21,7 @@
       - release-notes-jobs-python3
     check:
       jobs:
-        - openstack-ansible-lxd-ubuntu-xenial
+        - openstack-ansible-lxd-ubuntu-bionic
     gate:
       jobs:
-        - openstack-ansible-lxd-ubuntu-xenial
+        - openstack-ansible-lxd-ubuntu-bionic