The purpose of this spec is to add support for the Xen Hypervisor to OpenStack-Ansible. This will allow the use of Xen as an option on OpenStack compute nodes.
Xen is a tested and supported hypervisor in OpenStack. It is used in some of the largest public clouds today and would make a good addition to OpenStack-Ansible. Support for Xen exists in the OpenStack Libvirt Driver today so implementation should not be difficult.
The primary change is to add support in OpenStack-Ansible for Xen on CentOS 7, Ubuntu 16.04, and Ubuntu 14.04 (by using UCA repos). The necessary changes for Xen to work with OpenStack are in Xen 4.5.1 and Libvirt 1.2.15. This blueprint covers deploying the nova-xen compute driver with the standard networking agents that OpenStack-Ansible supports.
The proposed changes include:
See the Work Items for the playback/role impact. References to nova_virt_type will be updated to reflect a ‘xen’ option.
None. The xen driver is new for OpenStack-Ansible, and as such has no upgrade impact.
End users will be able to deploy compute nodes using the Xen virt driver.
Xen specific configuration options will be added to the openstack-ansible-os_nova role.
When support for Xen as a virt driver is added these config options will be available for use; however it is expected that Xen support will be disabled by default, requiring that deployers explicitly enable Xen support and configure hosts for OpenStack-Ansible to use.
Documentation of these new configuration items will be provided and a set of defaults will also be provided. The Xen virt driver has limited its configuration to be minimal, so the operators should only have a few required options to set when Xen is selected as the virt driver.
The existing development team will be asked for reviews and approvals of the change sets. The Xen driver team will do the necessary implementation and support of this function.
Multiple changes would be needed:
A new test-install-nova-xen.yml will be created for validating the new xen playbooks within the openstack-ansible-os_nova project.
Documentation covering how to enable and configure Xen support will be added to the user guide.
Xen and OpenStack required versions: http://wiki.xenproject.org/wiki/OpenStack_CI_Loop_for_Xen-Libvirt
Multi-platform Host OS Enablement: https://blueprints.launchpad.net/openstack-ansible/+spec/multi-platform-host