2294ed15a3
As part of the installation guide improvement project, I performed the following operations on the architecture chapter: 1) Added new diagrams for example architectures supported by the the installation guide. 2) Increased detail of node function descriptions. 3) Removed potentially confusing and overwhelming logical architecture diagram. 4) Clarified phrasing and wording. The contents of this chapter rely on other portions of the guide subject to change during this project and may need additional updates. Change-Id: I9b887f49a7d3ec94efc748a9056ec3a643ac7899 Partial-Bug: #1291071 Implements: blueprint networking-install-guide-improvements
42 lines
1.9 KiB
XML
42 lines
1.9 KiB
XML
<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="image-service-overview">
|
|
<title>Image Service overview</title>
|
|
<para>The Image Service includes the following
|
|
components:</para>
|
|
<itemizedlist>
|
|
<listitem>
|
|
<para><systemitem class="service">glance-api</systemitem>.
|
|
Accepts Image API calls for image discovery, retrieval,
|
|
and storage.</para>
|
|
</listitem>
|
|
<listitem>
|
|
<para><systemitem class="service"
|
|
>glance-registry</systemitem>. Stores, processes, and
|
|
retrieves metadata about images. Metadata includes items such
|
|
as size and type.</para>
|
|
</listitem>
|
|
<listitem>
|
|
<para>Database. Stores image metadata. You can choose your
|
|
database depending on your preference. Most deployments
|
|
use MySQL or SQlite.</para>
|
|
</listitem>
|
|
<listitem>
|
|
<para>Storage repository for image files. The Image Service
|
|
supports a variety of repositories including normal file systems,
|
|
Object Storage, RADOS block devices, HTTP, and Amazon S3. Some
|
|
types of repositories support only read-only usage.</para>
|
|
</listitem>
|
|
</itemizedlist>
|
|
<para>A number of periodic processes run on the Image Service to
|
|
support caching. Replication services ensures consistency and
|
|
availability through the cluster. Other periodic processes
|
|
include auditors, updaters, and reapers.</para>
|
|
<para>As shown in <xref linkend="conceptual-architecture"/>, the Image
|
|
Service is central to the overall IaaS picture. It accepts API
|
|
requests for images or image metadata from end users or
|
|
Compute components and can store its disk files in the Object
|
|
Storage Service.</para>
|
|
</section>
|