Simplify Openstack services configuration possibilities

Actually Openstack services configuration can be overriden using many
files:
- /etc/kolla/config/<< service name >>/<< config file >>
- /etc/kolla/config/<< service name >>/<<host>>/<< config file >>
- /etc/kolla/config/global.conf
- /etc/kolla/config/database.conf
- /etc/kolla/config/messaging.conf

Only per-service configuration is actually documented here:
https://github.com/openstack/kolla-ansible/blob/master/doc/advanced-configuration.rst#L164

Allowing to globally modify service configuration can be perform too,
but it can be done in 3 different manners, all not documented:
- /etc/kolla/config/global.conf
- /etc/kolla/config/database.conf
- /etc/kolla/config/messaging.conf

database.conf and messaging.conf seems redundant with global.conf.
In order to simplify codebase it seems logical to remove them.

Documentation has been added for overriding configuration globally and
release note has been added too.

Closes-Bug: #1682479
Change-Id: I5d922dfc0d938173bad34ac64e490b78db1b7e31

ansible/roles/aodh/tasks/config.yml

@@ -31,8 +31,6 @@
     sources:
       - "{{ role_path }}/templates/aodh.conf.j2"
       - "{{ node_custom_config }}/global.conf"
-      - "{{ node_custom_config }}/database.conf"
-      - "{{ node_custom_config }}/messaging.conf"
       - "{{ node_custom_config }}/aodh.conf"
       - "{{ node_custom_config }}/aodh/{{ item.key }}.conf"
       - "{{ node_custom_config }}/aodh/{{ inventory_hostname }}/aodh.conf"

ansible/roles/barbican/tasks/config.yml

@@ -67,8 +67,6 @@
     sources:
       - "{{ role_path }}/templates/barbican.conf.j2"
       - "{{ node_custom_config }}/global.conf"
-      - "{{ node_custom_config }}/database.conf"
-      - "{{ node_custom_config }}/messaging.conf"
       - "{{ node_custom_config }}/barbican.conf"
       - "{{ node_custom_config }}/barbican/{{ item.key }}.conf"
       - "{{ node_custom_config }}/barbican/{{ inventory_hostname }}/barbican.conf"

ansible/roles/ceilometer/tasks/config.yml

@@ -30,8 +30,6 @@
     sources:
       - "{{ role_path }}/templates/ceilometer.conf.j2"
       - "{{ node_custom_config }}/global.conf"
-      - "{{ node_custom_config }}/database.conf"
-      - "{{ node_custom_config }}/messaging.conf"
       - "{{ node_custom_config }}/ceilometer.conf"
       - "{{ node_custom_config }}/ceilometer/{{ item.key }}.conf"
       - "{{ node_custom_config }}/ceilometer/{{ inventory_hostname }}/ceilometer.conf"

ansible/roles/cinder/tasks/config.yml

@@ -48,8 +48,6 @@
     sources:
       - "{{ role_path }}/templates/cinder.conf.j2"
       - "{{ node_custom_config }}/global.conf"
-      - "{{ node_custom_config }}/database.conf"
-      - "{{ node_custom_config }}/messaging.conf"
       - "{{ node_custom_config }}/cinder.conf"
       - "{{ node_custom_config }}/cinder/{{ item.key }}.conf"
       - "{{ node_custom_config }}/cinder/{{ inventory_hostname }}/cinder.conf"

ansible/roles/cloudkitty/tasks/config.yml

@@ -29,8 +29,6 @@
     sources:
       - "{{ role_path }}/templates/cloudkitty.conf.j2"
       - "{{ node_custom_config }}/global.conf"
-      - "{{ node_custom_config }}/database.conf"
-      - "{{ node_custom_config }}/messaging.conf"
       - "{{ node_custom_config }}/cloudkitty.conf"
       - "{{ node_custom_config }}/cloudkitty/{{ item.key }}.conf"
       - "{{ node_custom_config }}/cloudkitty/{{ inventory_hostname }}/cloudkitty.conf"

ansible/roles/congress/tasks/config.yml

@@ -26,8 +26,6 @@
     sources:
       - "{{ role_path }}/templates/congress.conf.j2"
       - "{{ node_custom_config }}/global.conf"
-      - "{{ node_custom_config }}/database.conf"
-      - "{{ node_custom_config }}/messaging.conf"
       - "{{ node_custom_config }}/congress.conf"
       - "{{ node_custom_config }}/congress/{{ item.key }}.conf"
       - "{{ node_custom_config }}/congress/{{ inventory_hostname }}/congress.conf"

ansible/roles/designate/tasks/config.yml

@@ -33,8 +33,6 @@
     sources:
       - "{{ role_path }}/templates/designate.conf.j2"
       - "{{ node_custom_config }}/global.conf"
-      - "{{ node_custom_config }}/database.conf"
-      - "{{ node_custom_config }}/messaging.conf"
       - "{{ node_custom_config }}/designate.conf"
       - "{{ node_custom_config }}/designate/{{ item.key }}.conf"
       - "{{ node_custom_config }}/designate/{{ inventory_hostname }}/designate.conf"

ansible/roles/freezer/tasks/config.yml

@@ -40,8 +40,6 @@
     sources:
       - "{{ role_path }}/templates/freezer-api.conf.j2"
       - "{{ node_custom_config }}/global.conf"
-      - "{{ node_custom_config }}/database.conf"
-      - "{{ node_custom_config }}/messaging.conf"
       - "{{ node_custom_config }}/freezer.conf"
       - "{{ node_custom_config }}/freezer/{{ item.key }}.conf"
       - "{{ node_custom_config }}/freezer/{{ inventory_hostname }}/{{ item.key }}.conf"

ansible/roles/glance/tasks/config.yml

@@ -29,8 +29,6 @@
     sources:
       - "{{ role_path }}/templates/{{ item.key }}.conf.j2"
       - "{{ node_custom_config }}/global.conf"
-      - "{{ node_custom_config }}/database.conf"
-      - "{{ node_custom_config }}/messaging.conf"
       - "{{ node_custom_config }}/glance.conf"
       - "{{ node_custom_config }}/glance/{{ item.key }}.conf"
       - "{{ node_custom_config }}/glance/{{ inventory_hostname }}/{{ item.key }}.conf"

ansible/roles/gnocchi/tasks/config.yml

@@ -30,8 +30,6 @@
     sources:
       - "{{ role_path }}/templates/gnocchi.conf.j2"
       - "{{ node_custom_config }}/global.conf"
-      - "{{ node_custom_config }}/database.conf"
-      - "{{ node_custom_config }}/messaging.conf"
       - "{{ node_custom_config }}/gnocchi.conf"
       - "{{ node_custom_config }}/gnocchi/{{ item.key }}.conf"
       - "{{ node_custom_config }}/gnocchi/{{ inventory_hostname }}/gnocchi.conf"

ansible/roles/heat/tasks/config.yml

@@ -37,8 +37,6 @@
     sources:
       - "{{ role_path }}/templates/heat.conf.j2"
       - "{{ node_custom_config }}/global.conf"
-      - "{{ node_custom_config }}/database.conf"
-      - "{{ node_custom_config }}/messaging.conf"
       - "{{ node_custom_config }}/heat.conf"
       - "{{ node_custom_config }}/heat/{{ item.key }}.conf"
       - "{{ node_custom_config }}/heat/{{ inventory_hostname }}/heat.conf"

ansible/roles/ironic/tasks/config.yml

@@ -29,8 +29,6 @@
     sources:
       - "{{ role_path }}/templates/ironic.conf.j2"
       - "{{ node_custom_config }}/global.conf"
-      - "{{ node_custom_config }}/database.conf"
-      - "{{ node_custom_config }}/messaging.conf"
       - "{{ node_custom_config }}/ironic.conf"
       - "{{ node_custom_config }}/ironic/{{ item }}.conf"
       - "{{ node_custom_config }}/ironic/{{ inventory_hostname }}/ironic.conf"
@@ -46,8 +44,6 @@
     sources:
       - "{{ role_path }}/templates/ironic-inspector.conf.j2"
       - "{{ node_custom_config }}/global.conf"
-      - "{{ node_custom_config }}/database.conf"
-      - "{{ node_custom_config }}/messaging.conf"
       - "{{ node_custom_config }}/ironic-inspector.conf"
       - "{{ node_custom_config }}/ironic-inspector/inspector.conf"
       - "{{ node_custom_config }}/ironic-inspector/{{ inventory_hostname }}/inspector.conf"

ansible/roles/karbor/tasks/config.yml

@@ -30,8 +30,6 @@
     sources:
       - "{{ role_path }}/templates/karbor.conf.j2"
       - "{{ node_custom_config }}/global.conf"
-      - "{{ node_custom_config }}/database.conf"
-      - "{{ node_custom_config }}/messaging.conf"
       - "{{ node_custom_config }}/karbor.conf"
       - "{{ node_custom_config }}/karbor/{{ item.key }}.conf"
       - "{{ node_custom_config }}/karbor/{{ inventory_hostname }}/karbor.conf"

ansible/roles/keystone/tasks/config.yml

@@ -40,8 +40,6 @@
     sources:
       - "{{ role_path }}/templates/keystone.conf.j2"
       - "{{ node_custom_config }}/global.conf"
-      - "{{ node_custom_config }}/database.conf"
-      - "{{ node_custom_config }}/messaging.conf"
       - "{{ node_custom_config }}/keystone.conf"
       - "{{ node_custom_config }}/keystone/{{ item.key }}.conf"
       - "{{ node_custom_config }}/keystone/{{ inventory_hostname }}/keystone.conf"

ansible/roles/kuryr/tasks/config.yml

@@ -28,8 +28,6 @@
     sources:
       - "{{ role_path }}/templates/kuryr.conf.j2"
       - "{{ node_custom_config }}/global.conf"
-      - "{{ node_custom_config }}/database.conf"
-      - "{{ node_custom_config }}/messaging.conf"
       - "{{ node_custom_config }}/kuryr.conf"
       - "{{ node_custom_config }}/kuryr/{{ item.key }}.conf"
       - "{{ node_custom_config }}/kuryr/{{ inventory_hostname }}/{{ item.key }}.conf"

ansible/roles/magnum/tasks/config.yml

@@ -29,8 +29,6 @@
     sources:
       - "{{ role_path }}/templates/magnum.conf.j2"
       - "{{ node_custom_config }}/global.conf"
-      - "{{ node_custom_config }}/database.conf"
-      - "{{ node_custom_config }}/messaging.conf"
       - "{{ node_custom_config }}/magnum.conf"
       - "{{ node_custom_config }}/magnum/{{ item.key }}.conf"
       - "{{ node_custom_config }}/magnum/{{ inventory_hostname }}/magnum.conf"

ansible/roles/manila/tasks/config.yml

@@ -28,8 +28,6 @@
     sources:
       - "{{ role_path }}/templates/manila.conf.j2"
       - "{{ node_custom_config }}/global.conf"
-      - "{{ node_custom_config }}/database.conf"
-      - "{{ node_custom_config }}/messaging.conf"
       - "{{ node_custom_config }}/manila.conf"
       - "{{ node_custom_config }}/manila/{{ item.key }}.conf"
       - "{{ node_custom_config }}/manila/{{ inventory_hostname }}/manila.conf"
@@ -54,8 +52,6 @@
       - "{{ role_path }}/templates/manila.conf.j2"
       - "{{ role_path }}/templates/manila-share.conf.j2"
       - "{{ node_custom_config }}/global.conf"
-      - "{{ node_custom_config }}/database.conf"
-      - "{{ node_custom_config }}/messaging.conf"
       - "{{ node_custom_config }}/manila.conf"
       - "{{ node_custom_config }}/{{ item }}.conf"
       - "{{ node_custom_config }}/manila/{{ item }}.conf"

ansible/roles/mistral/tasks/config.yml

@@ -26,8 +26,6 @@
     sources:
       - "{{ role_path }}/templates/mistral.conf.j2"
       - "{{ node_custom_config }}/global.conf"
-      - "{{ node_custom_config }}/database.conf"
-      - "{{ node_custom_config }}/messaging.conf"
       - "{{ node_custom_config }}/mistral.conf"
       - "{{ node_custom_config }}/mistral/{{ item.key }}.conf"
       - "{{ node_custom_config }}/mistral/{{ inventory_hostname }}/mistral.conf"

ansible/roles/murano/tasks/config.yml

@@ -23,8 +23,6 @@
     sources:
       - "{{ role_path }}/templates/murano.conf.j2"
       - "{{ node_custom_config }}/global.conf"
-      - "{{ node_custom_config }}/database.conf"
-      - "{{ node_custom_config }}/messaging.conf"
       - "{{ node_custom_config }}/murano.conf"
       - "{{ node_custom_config }}/murano/{{ item }}.conf"
       - "{{ node_custom_config }}/murano/{{ inventory_hostname }}/murano.conf"

ansible/roles/neutron/tasks/config-neutron-fake.yml

@@ -24,8 +24,6 @@
     sources:
       - "{{ role_path }}/templates/neutron.conf.j2"
       - "{{ node_custom_config }}/global.conf"
-      - "{{ node_custom_config }}/database.conf"
-      - "{{ node_custom_config }}/messaging.conf"
       - "{{ node_custom_config }}/neutron.conf"
       - "{{ node_custom_config }}/neutron/{{ item }}.conf"
       - "{{ node_custom_config }}/neutron/{{ inventory_hostname }}/neutron.conf"

ansible/roles/neutron/tasks/config.yml

@@ -52,8 +52,6 @@
     sources:
       - "{{ role_path }}/templates/neutron.conf.j2"
       - "{{ node_custom_config }}/global.conf"
-      - "{{ node_custom_config }}/database.conf"
-      - "{{ node_custom_config }}/messaging.conf"
       - "{{ node_custom_config }}/neutron.conf"
       - "{{ node_custom_config }}/neutron/{{ item.key }}.conf"
       - "{{ node_custom_config }}/neutron/{{ inventory_hostname }}/neutron.conf"

ansible/roles/nova/tasks/config-nova-fake.yml

@@ -23,8 +23,6 @@
     sources:
       - "{{ role_path }}/templates/nova.conf.j2"
       - "{{ node_custom_config }}/global.conf"
-      - "{{ node_custom_config }}/database.conf"
-      - "{{ node_custom_config }}/messaging.conf"
       - "{{ node_custom_config }}/nova.conf"
       - "{{ node_custom_config }}/nova/{{ item }}.conf"
       - "{{ node_custom_config }}/nova/{{ inventory_hostname }}/nova.conf"

ansible/roles/nova/tasks/config.yml

@@ -50,8 +50,6 @@
     sources:
       - "{{ role_path }}/templates/nova.conf.j2"
       - "{{ node_custom_config }}/global.conf"
-      - "{{ node_custom_config }}/database.conf"
-      - "{{ node_custom_config }}/messaging.conf"
       - "{{ node_custom_config }}/nova.conf"
       - "{{ node_custom_config }}/nova/{{ item.key }}.conf"
       - "{{ node_custom_config }}/nova/{{ inventory_hostname }}/nova.conf"

ansible/roles/octavia/tasks/config.yml

@@ -28,8 +28,6 @@
     sources:
       - "{{ role_path }}/templates/octavia.conf.j2"
       - "{{ node_custom_config }}/global.conf"
-      - "{{ node_custom_config }}/database.conf"
-      - "{{ node_custom_config }}/messaging.conf"
       - "{{ node_custom_config }}/octavia.conf"
       - "{{ node_custom_config }}/octavia/{{ item.key }}.conf"
       - "{{ node_custom_config }}/octavia/{{ inventory_hostname }}/octavia.conf"

ansible/roles/panko/tasks/config.yml

@@ -28,8 +28,6 @@
     sources:
       - "{{ role_path }}/templates/panko.conf.j2"
       - "{{ node_custom_config }}/global.conf"
-      - "{{ node_custom_config }}/database.conf"
-      - "{{ node_custom_config }}/messaging.conf"
       - "{{ node_custom_config }}/panko.conf"
       - "{{ node_custom_config }}/panko/{{ item.key }}.conf"
       - "{{ node_custom_config }}/panko/{{ inventory_hostname }}/{{ item.key }}.conf"

ansible/roles/sahara/tasks/config.yml

@@ -29,8 +29,6 @@
     sources:
       - "{{ role_path }}/templates/sahara.conf.j2"
       - "{{ node_custom_config }}/global.conf"
-      - "{{ node_custom_config }}/database.conf"
-      - "{{ node_custom_config }}/messaging.conf"
       - "{{ node_custom_config }}/sahara.conf"
       - "{{ node_custom_config }}/sahara/{{ item.key }}.conf"
       - "{{ node_custom_config }}/sahara/{{ inventory_hostname }}/sahara.conf"

ansible/roles/searchlight/tasks/config.yml

@@ -26,7 +26,6 @@
     sources:
       - "{{ role_path }}/templates/searchlight.conf.j2"
       - "{{ node_custom_config }}/global.conf"
-      - "{{ node_custom_config }}/messaging.conf"
       - "{{ node_custom_config }}/searchlight.conf"
       - "{{ node_custom_config }}/searchlight/{{ inventory_hostname }}/searchlight.conf"
     dest: "{{ node_config_directory }}/{{ item.key }}/searchlight.conf"

ansible/roles/senlin/tasks/config.yml

@@ -29,8 +29,6 @@
     sources:
       - "{{ role_path }}/templates/senlin.conf.j2"
       - "{{ node_custom_config }}/global.conf"
-      - "{{ node_custom_config }}/database.conf"
-      - "{{ node_custom_config }}/messaging.conf"
       - "{{ node_custom_config }}/senlin.conf"
       - "{{ node_custom_config }}/senlin/{{ item.key }}.conf"
       - "{{ node_custom_config }}/senlin/{{ inventory_hostname }}/senlin.conf"

ansible/roles/solum/tasks/config.yml

@@ -31,8 +31,6 @@
     sources:
       - "{{ role_path }}/templates/solum.conf.j2"
       - "{{ node_custom_config }}/global.conf"
-      - "{{ node_custom_config }}/database.conf"
-      - "{{ node_custom_config }}/messaging.conf"
       - "{{ node_custom_config }}/solum.conf"
       - "{{ node_custom_config }}/solum/{{ item.key }}.conf"
       - "{{ node_custom_config }}/solum/{{ inventory_hostname }}/solum.conf"

ansible/roles/tacker/tasks/config.yml

@@ -29,8 +29,6 @@
     sources:
       - "{{ role_path }}/templates/tacker.conf.j2"
       - "{{ node_custom_config }}/global.conf"
-      - "{{ node_custom_config }}/database.conf"
-      - "{{ node_custom_config }}/messaging.conf"
       - "{{ node_custom_config }}/tacker.conf"
       - "{{ node_custom_config }}/tacker/{{ item.key }}.conf"
       - "{{ node_custom_config }}/tacker/{{ inventory_hostname }}/tacker.conf"

ansible/roles/trove/tasks/config.yml

@@ -42,8 +42,6 @@
     sources:
       - "{{ role_path }}/templates/trove.conf.j2"
       - "{{ node_custom_config }}/global.conf"
-      - "{{ node_custom_config }}/database.conf"
-      - "{{ node_custom_config }}/messaging.conf"
       - "{{ node_custom_config }}/trove.conf"
       - "{{ node_custom_config }}/trove/{{ item.key }}.conf"
       - "{{ node_custom_config }}/trove/{{ inventory_hostname }}/trove.conf"

ansible/roles/watcher/tasks/config.yml

@@ -30,8 +30,6 @@
     sources:
       - "{{ role_path }}/templates/watcher.conf.j2"
       - "{{ node_custom_config }}/global.conf"
-      - "{{ node_custom_config }}/database.conf"
-      - "{{ node_custom_config }}/messaging.conf"
       - "{{ node_custom_config }}/watcher.conf"
       - "{{ node_custom_config }}/watcher/{{ item.key }}.conf"
       - "{{ node_custom_config }}/watcher/{{ inventory_hostname }}/watcher.conf"

ansible/roles/zun/tasks/config.yml

@@ -27,8 +27,6 @@
     sources:
       - "{{ role_path }}/templates/zun.conf.j2"
       - "{{ node_custom_config }}/global.conf"
-      - "{{ node_custom_config }}/database.conf"
-      - "{{ node_custom_config }}/messaging.conf"
       - "{{ node_custom_config }}/zun.conf"
       - "{{ node_custom_config }}/zun/{{ item.key }}.conf"
       - "{{ node_custom_config }}/zun/{{ inventory_hostname }}/zun.conf"

doc/source/user/advanced-configuration.rst

@@ -181,6 +181,17 @@ on host myhost, the operator needs to create file
    [DEFAULT]
    ram_allocation_ratio = 5.0
 
+Kolla allows the operator to override configuration globally for all services.
+It will look for a file called ``/etc/kolla/config/global.conf``.
+
+For example to modify database pool size connection for all services, the
+operator needs to create ``/etc/kolla/config/global.conf`` with content:
+
+::
+
+   [database]
+   max_pool_size = 100
+
 The operator can make these changes after services were already deployed by
 using following command:
 

releasenotes/notes/simplify-global-config-generation-8f42cea604ba1cf2.yaml

@@ -0,0 +1,6 @@
+---
+upgrade:
+  - |
+    The following files /etc/kolla/config/database.conf and /etc/kolla/config/messaging.conf
+    used to generate Openstack services config files are redundant with /etc/kolla/config/global.conf.
+    They have been removed in order to simplify codebase.