5a56683f8d
Change-Id: I4f5b10529fd40252f2af2382e2361950b5e686a9 Closes-Bug: #1557968
40 lines
1.7 KiB
ReStructuredText
40 lines
1.7 KiB
ReStructuredText
====================
|
|
Logical architecture
|
|
====================
|
|
|
|
To design, deploy, and configure OpenStack, administrators must
|
|
understand the logical architecture.
|
|
|
|
As shown in :ref:`get_started_conceptual_architecture`, OpenStack consists of
|
|
several independent parts, named the OpenStack services. All services
|
|
authenticate through a common Identity service. Individual services interact
|
|
with each other through public APIs, except where privileged administrator
|
|
commands are necessary.
|
|
|
|
Internally, OpenStack services are composed of several processes. All
|
|
services have at least one API process, which listens for API requests,
|
|
preprocesses them and passes them on to other parts of the service. With
|
|
the exception of the Identity service, the actual work is done by
|
|
distinct processes.
|
|
|
|
For communication between the processes of one service, an AMQP message
|
|
broker is used. The service's state is stored in a database. When
|
|
deploying and configuring your OpenStack cloud, you can choose among
|
|
several message broker and database solutions, such as RabbitMQ, Qpid,
|
|
MySQL, MariaDB, and SQLite.
|
|
|
|
Users can access OpenStack via the web-based user interface implemented
|
|
by the :ref:`get_started_dashboard`, via `command-line
|
|
clients <http://docs.openstack.org/cli-reference/>`__ and by
|
|
issuing API requests through tools like browser plug-ins or :command:`curl`.
|
|
For applications, `several SDKs <http://developer.openstack.org/#sdk>`__
|
|
are available. Ultimately, all these access methods issue REST API calls
|
|
to the various OpenStack services.
|
|
|
|
The following diagram shows the most common, but not the only possible,
|
|
architecture for an OpenStack cloud:
|
|
|
|
.. image:: figures/openstack-arch-kilo-logical-v1.png
|
|
:alt: Logical architecture
|
|
:width: 100%
|