openstack-manuals/doc/arch-design/specialized/section_openstack_on_openstack_specialized.xml
RobiJoe 1c76ef3f4a Architecture Design Guide - Specialized Chapter edits
Small scale edits to the examples appearing in the specialized
chapter. Correct typos.

Change-Id: I08d80b5268beafcae5fa4ea7120839c341ce3481
Implements: blueprint arch-guide
2015-08-18 09:01:26 +10:00

81 lines
3.8 KiB
XML

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE section [
<!ENTITY % openstack SYSTEM "../../common/entities/openstack.ent">
%openstack;
]>
<section xmlns="http://docbook.org/ns/docbook"
xmlns:xi="http://www.w3.org/2001/XInclude"
xmlns:xlink="http://www.w3.org/1999/xlink"
version="5.0"
xml:id="arch-guide-openstack-on-openstack">
<?dbhtml stop-chunking?>
<title>OpenStack on OpenStack</title>
<para>In some cases, users may run OpenStack nested on top
of another OpenStack cloud. This scenario describes how to
manage and provision complete OpenStack environments on instances
supported by hypervisors and servers, which an underlying OpenStack
environment controls.</para>
<para>Public cloud providers can use this technique to manage the
upgrade and maintenance process on complete OpenStack environments.
Developers and those testing OpenStack can also use this
technique to provision their own OpenStack environments on
available OpenStack Compute resources, whether public or
private.</para>
<section xml:id="challenges-for-nested-cloud">
<title>Challenges</title>
<para>The network aspect of deploying a nested cloud is the most
complicated aspect of this architecture. You must expose VLANs
to the physical ports on which the underlying cloud runs because
the bare metal cloud owns all the
hardware. You must also expose them to the nested
levels as well. Alternatively, you can use the network overlay
technologies on the OpenStack environment running on the host
OpenStack environment to provide the required software defined
networking for the deployment.</para>
</section>
<section xml:id="hypervisor-nested-cloud">
<title>Hypervisor</title>
<para>In this example architecture, consider which
approach you should take to provide a nested
hypervisor in OpenStack. This decision influences which
operating systems you use for the deployment of the nested
OpenStack deployments.</para>
</section>
<section xml:id="possible-solutions-nested-cloud-deployment">
<title>Possible solutions: deployment</title>
<para>Deployment of a full stack can be challenging but you can mitigate
this difficulty by creating a Heat template to deploy the
entire stack, or a configuration management system. After creating
the Heat template, you can automate the deployment of additional stacks.</para>
<para>The OpenStack-on-OpenStack project (<glossterm>TripleO</glossterm>)
addresses this issue. Currently, however, the project does
not completely cover nested stacks. For more information, see
<link xlink:href="https://wiki.openstack.org/wiki/TripleO">
https://wiki.openstack.org/wiki/TripleO</link>.</para>
</section>
<section xml:id="possible-solutions-nested-cloud-hypervisor">
<title>Possible solutions: hypervisor</title>
<para>In the case of running TripleO, the underlying OpenStack
cloud deploys the Compute nodes as bare-metal. You then deploy
OpenStack on these Compute bare-metal servers with the
appropriate hypervisor, such as KVM.</para>
<para>In the case of running smaller OpenStack clouds for testing
purposes, where performance is not a critical factor, you can use
QEMU instead. It is also possible to run a KVM hypervisor in an instance
(see <link xlink:href="http://davejingtian.org/2014/03/30/nested-kvm-just-for-fun/">
http://davejingtian.org/2014/03/30/nested-kvm-just-for-fun/</link>),
though this is not a supported configuration, and could be a
complex solution for such a use case.</para>
</section>
<section xml:id="nested-cloud-diagram">
<title>Diagram</title>
<para>
<mediaobject>
<imageobject>
<imagedata contentwidth="4in" fileref="../figures/Specialized_OOO.png"/>
</imageobject>
</mediaobject>
</para>
</section>
</section>