Multiple Regions Deployment with Kolla¶
This section describes how to perform a basic multiple region deployment
with Kolla. A basic multiple region deployment consists of separate
OpenStack installations 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 internal endpoint (for example, 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 is specifications of multiple regions deployment at 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
whether it is an all-in-one or multinode deployment (see
Quick Start for deployment/evaluation). 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 known as RegionOne, that is hidden 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_internal_url: "{{ internal_protocol }}://{{ kolla_internal_fqdn_r1 }}:{{ keystone_public_port }}"
openstack_auth:
auth_url: "{{ keystone_internal_url }}"
username: "{{ keystone_admin_user }}"
password: "{{ keystone_admin_password }}"
user_domain_name: "{{ default_user_domain_name }}"
project_name: "{{ keystone_admin_project }}"
domain_name: "default"
Note
If the kolla_internal_vip_address
and/or the
kolla_external_vip_address
reside on the same subnet as
kolla_internal_fqdn_r1
, you should set the
keepalived_virtual_router_id
value in the /etc/kolla/globals.yml
to a unique number.
Configuration files of cinder,nova,neutron,glance… have to be updated to
contact RegionOne’s Keystone. Fortunately, Kolla allows you to override all
configuration files at the same time thanks to the
node_custom_config
variable (see OpenStack Service Configuration in Kolla). To do so,
create a global.conf
file with the following content:
[keystone_authtoken]
www_authenticate_uri = {{ keystone_internal_url }}
auth_url = {{ keystone_internal_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_internal_url }}
The Heat section inside the configuration file also
has to be updated to contact RegionOne’s Keystone. So create, in the same
directory, a heat.conf
file with below content:
[trustee]
www_authenticate_uri = {{ keystone_internal_url }}
auth_url = {{ keystone_internal_url }}
[ec2authtoken]
www_authenticate_uri = {{ keystone_internal_url }}
[clients_keystone]
www_authenticate_uri = {{ keystone_internal_url }}
The Ceilometer section inside the configuration file also
has to be updated to contact RegionOne’s Keystone. So create, in the same
directory, a ceilometer.conf
file with below content:
[service_credentials]
auth_url = {{ keystone_internal_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.