<?xml version="1.0" encoding="UTF-8"?>
<chapter 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="ch_glance">
  <title>Add the Image Service</title>
  <para>The OpenStack Image Service (glance) enables users to discover,
    register, and retrieve virtual machine images. It offers a <glossterm
      baseform="RESTful">REST</glossterm> API that enables you to
    query virtual machine image metadata and retrieve an actual image.
    You can store virtual machine images made available through the
    Image Service in a variety of locations, from simple file systems
    to object-storage systems like OpenStack Object Storage.</para>
  <important>
    <para>For simplicity, this guide describes configuring the Image Service to
      use the <literal>file</literal> back end, which uploads and stores in a
      directory on the controller node hosting the Image Service. By
      default, this directory is <filename>/var/lib/glance/images/</filename>.
    </para>
    <para>Before you proceed, ensure that the controller node has at least
      several gigabytes of space available in this directory.</para>
    <para>For information on requirements for other back ends, see <link
        xlink:href="http://docs.openstack.org/trunk/config-reference/content/ch_configuring-openstack-image-service.html"
          ><citetitle>Configuration
      Reference</citetitle></link>.</para>
  </important>
  <xi:include href="../common/section_getstart_image.xml"/>
  <xi:include href="section_glance-install.xml"/>
  <xi:include href="section_glance-verify.xml"/>
</chapter>