openstack-manuals/doc/common/section_getstart_image.xml
Christian Berendt b2235bf3fb Unified the syntax of the XML root element (common)
Execluded all XML files in the directory doc/common/tables because
they are autogenerated.

The XML root element of Docbook XML files should match the following
format:

<ELEMENT 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="THE_XML_ID_OF_THE_ELEMENT">

Change-Id: If12091be81ec8b2e6e53bfcb4c3a883a65e24736
2014-07-09 22:23:03 +02:00

51 lines
2.5 KiB
XML

<?xml version="1.0" encoding="UTF-8"?>
<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 is central to Infrastructure-as-a-Service (IaaS)
as shown in <xref linkend="conceptual-architecture"/>. It accepts API requests
for disk or server images, and image metadata from end users or OpenStack Compute
components. It also supports the storage of disk or server images on various
repository types, including OpenStack Object Storage.
</para>
<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 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>
</section>