openstack-manuals/doc/common/section_getstart_image.xml
Darren 3981735acd Edited Services sections of Admin Guide
Edit wording; changed term/description lists to variable lists as per writing
conventions

backport: none
Partial-Bug: #1251195

Change-Id: I3b7f3fedafa79ab64f75260fcd3c5daa7cbb5e34
2014-05-23 12:55:20 +10:00

48 lines
2.3 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>OpenStack Image Service</title>
<para>The OpenStack Image Service includes the following
components:</para>
<variablelist>
<varlistentry>
<term><systemitem class="service">glance-api</systemitem></term>
<listitem><para>Accepts Image API calls for image discovery,
retrieval, and storage.</para></listitem>
</varlistentry>
<varlistentry>
<term><systemitem class="service">glance-registry</systemitem></term>
<listitem><para>Stores, processes, and retrieves metadata about
images. Metadata includes items such as size and type.</para>
<note><title>Security note</title>
<para>The registry is a private internal service meant for use
by OpenStack Image Service. Do not disclose it to
users.</para></note>
</listitem>
</varlistentry>
<varlistentry>
<term>Database</term>
<listitem><para>Stores image metadata and you can choose your database
depending on your preference. Most deployments use MySQL or
SQlite.</para></listitem>
</varlistentry>
<varlistentry>
<term>Storage repository for image files</term>
<listitem><para>Various repository types are supported including
normal file systems, Object Storage, RADOS block devices, HTTP, and
Amazon S3. Note that some repositories will only support
read-only usage.</para></listitem>
</varlistentry>
</variablelist>
<para>A number of periodic processes run on the OpenStack Image Service to
support caching. Replication services ensures consistency and
availability through the cluster. Other periodic processes
include auditors, updaters, and reapers.</para>
<para>The OpenStack Image Service is central to
infrastructure-as-a-service (IaaS) as shown in <xref
linkend="conceptual-architecture"/>. It accepts API requests for images
or image metadata from end users or OpenStack Compute components, and
can store its disk files in OpenStack Object Storage.</para>
</section>