Multiple Regions Deployment with Kolla¶
This section describes how to perform a basic multiple regions deployment
with Kolla. A basic multiple regions deployment consists of separate
OpenStack installation in two or more regions (RegionOne, RegionTwo, …)
with a shared Keystone and Horizon. The rest of this documentation assumes
Keystone and Horizon are deployed in RegionOne, and other regions have
access to the admin endpoint (i.e., kolla_internal_fqdn
) of RegionOne.
It also assumes that the operator knows the name of all OpenStack regions
in advance, and considers as many Kolla deployments as there are regions.
There are specifications of multiple regions deployment at: http://docs.openstack.org/arch-design/multi-site-architecture.html and https://wiki.openstack.org/wiki/Heat/Blueprints/Multi_Region_Support_for_Heat.
Deployment of the first region with Keystone and Horizon¶
Deployment of the first region results in a typical Kolla deployment
whenever, it is an all-in-one or multinode deployment (see
Quick Start). It only requires slight modifications in the
/etc/kolla/globals.yml
configuration file. First of all, ensure that
Keystone and Horizon are enabled:
enable_keystone: "yes"
enable_horizon: "yes"
Then, change the value of multiple_regions_names
to add names of other
regions. In this example, we consider two regions. The current one,
formerly knows as RegionOne, that is hided behind
openstack_region_name
variable, and the RegionTwo:
openstack_region_name: "RegionOne"
multiple_regions_names:
- "{{ openstack_region_name }}"
- "RegionTwo"
Note
Kolla uses these variables to create necessary endpoints into
Keystone so that services of other regions can access it. Kolla
also updates the Horizon local_settings
to support multiple
regions.
Finally, note the value of kolla_internal_fqdn
and run
kolla-ansible
. The kolla_internal_fqdn
value will be used by other
regions to contact Keystone. For the sake of this example, we assume the
value of kolla_internal_fqdn
is 10.10.10.254
.
Deployment of other regions¶
Deployment of other regions follows an usual Kolla deployment except that
OpenStack services connect to the RegionOne’s Keystone. This implies to
update the /etc/kolla/globals.yml
configuration file to tell Kolla how
to reach Keystone. In the following, kolla_internal_fqdn_r1
refers to
the value of kolla_internal_fqdn
in RegionOne:
kolla_internal_fqdn_r1: 10.10.10.254
keystone_admin_url: "{{ admin_protocol }}://{{ kolla_internal_fqdn_r1 }}:{{ keystone_admin_port }}/v3"
keystone_internal_url: "{{ internal_protocol }}://{{ kolla_internal_fqdn_r1 }}:{{ keystone_public_port }}/v3"
openstack_auth:
auth_url: "{{ admin_protocol }}://{{ kolla_internal_fqdn_r1 }}:{{ keystone_admin_port }}"
username: "admin"
password: "{{ keystone_admin_password }}"
project_name: "admin"
Configuration files of nova/neutron/glance… have to be updated to
contact RegionOne’s Keystone. Fortunately, Kolla offers to override all
configuration files at the same time thanks to the
node_custom_config
variable (see OpenStack Service Configuration in Kolla). This
implies to create a global.conf
file with the following content:
[keystone_authtoken]
auth_uri = {{ keystone_internal_url }}
auth_url = {{ keystone_admin_url }}
The Placement API section inside the nova configuration file also has
to be updated to contact RegionOne’s Keystone. So create, in the same
directory, a nova.conf
file with below content:
[placement]
auth_url = {{ keystone_admin_url }}
And link the directory that contains these files into the
/etc/kolla/globals.yml
:
node_custom_config: path/to/the/directory/of/global&nova_conf/
Also, change the name of the current region. For instance, RegionTwo:
openstack_region_name: "RegionTwo"
Finally, disable the deployment of Keystone and Horizon that are
unnecessary in this region and run kolla-ansible
:
enable_keystone: "no"
enable_horizon: "no"
The configuration is the same for any other region.