DNM ci_dcn_site: Add scaling down of a DCN site

playbooks/dcn.yml

@@ -63,6 +63,25 @@
         - _ceph_bootstrap_node != ''
       ansible.builtin.include_role:
         name: ci_dcn_site
+      when: cifmw_ci_dcn_site_scaledown_az is not defined or cifmw_ci_dcn_site_scaledown_az == ""
+
+    - name: The map for az0 contains all AZ backends
+      ansible.builtin.set_fact:
+        az_to_group_map:
+          az0: computes
+          az1: dcn1-computes
+          az2: dcn2-computes
+
+    - name: Scaledown the {{ cifmw_ci_dcn_site_scaledown_az }} site
+      vars:
+        _az_to_scaledown: "{{ cifmw_ci_dcn_site_scaledown_az }}"
+        _subnet: "subnet{{ (az_to_group_map | dict2items | map(attribute='key') | list)
+                           | ansible.utils.index_of('eq', cifmw_ci_dcn_site_scaledown_az) + 1 }}"
+        _group_name: "{{ az_to_group_map[cifmw_ci_dcn_site_scaledown_az] }}"
+        _group_hosts: "{{ groups[az_to_group_map[cifmw_ci_dcn_site_scaledown_az]] }}"
+      ansible.builtin.include_role:
+        name: ci_dcn_site
+      when: cifmw_ci_dcn_site_scaledown_az is defined and cifmw_ci_dcn_site_scaledown_az != ""
 
     - name: Find all created CRs
       ansible.builtin.find:

roles/ci_dcn_site/README.md

@@ -12,6 +12,7 @@ with a collocated Ceph cluster.
 ## Parameters
 
 * `_az`: The name of the availability zone for the AZ, e.g. `az1`
+* `_az_to_scaledown`: The name of the availability zone for the deployed AZ to be scale-downed.
 * `_group_name`: The name of the group of nodes to be deployed, e.g. `dcn1-computes`
 * `_subnet`: The name of the subnet the DCN site will use, e.g. `subnet2`
 * `_subnet_network_range`: The range of the subnet the DCN site will use, e.g. `192.168.133.0/24`

roles/ci_dcn_site/defaults/main.yml

@@ -26,3 +26,4 @@ ci_dcn_site_search_storagemgmt_network_names:
   - "storagemgmtdcn1"
   - "storagemgmtdcn2"
 cifmw_ci_dcn_site_enable_network_az: false
+_az_to_scaledown: ""

roles/ci_dcn_site/tasks/deploy_site.yml

@@ -0,0 +1,34 @@
+---
+# Copyright Red Hat, Inc.
+# All Rights Reserved.
+#
+# 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: Render and apply pre-ceph CRs in DCN context
+  ansible.builtin.include_tasks: pre-ceph.yml
+
+- name: Deploy Ceph in DCN context
+  ansible.builtin.include_tasks: ceph.yml
+
+- name: Render and apply post-ceph CRs in DCN context
+  ansible.builtin.include_tasks: post-ceph.yml
+
+- name: Run Nova cell discovery for new DCN hosts
+  kubernetes.core.k8s_exec:
+    api_key: "{{ _auth_results.openshift_auth.api_key }}"
+    namespace: openstack
+    pod: nova-cell0-conductor-0
+    command: nova-manage cell_v2 discover_hosts --verbose
+
+- name: Create new AZ and add new hosts to it
+  ansible.builtin.include_tasks: az.yml

roles/ci_dcn_site/tasks/main.yml

@@ -22,21 +22,10 @@
 - name: Set Network related facts
   ansible.builtin.include_tasks: set_network_facts.yml
 
-- name: Render and apply pre-ceph CRs in DCN context
-  ansible.builtin.include_tasks: pre-ceph.yml
+- name: Deploy a DCN site
+  ansible.builtin.include_tasks: deploy_site.yml
+  when: _az_to_scaledown == ""
 
-- name: Deploy Ceph in DCN context
-  ansible.builtin.include_tasks: ceph.yml
-
-- name: Render and apply post-ceph CRs in DCN context
-  ansible.builtin.include_tasks: post-ceph.yml
-
-- name: Run Nova cell discovery for new DCN hosts
-  kubernetes.core.k8s_exec:
-    api_key: "{{ _auth_results.openshift_auth.api_key }}"
-    namespace: openstack
-    pod: nova-cell0-conductor-0
-    command: nova-manage cell_v2 discover_hosts --verbose
-
-- name: Create new AZ and add new hosts to it
-  ansible.builtin.include_tasks: az.yml
+- name: Scale a DCN site down
+  ansible.builtin.include_tasks: scaledown_site.yml
+  when: _az_to_scaledown is defined and _az_to_scaledown != ""