diff --git a/doc/admin-guide-cloud/section_adding-images.xml b/doc/admin-guide-cloud/section_adding-images.xml
index 3fe215dbd0..8f966385d7 100644
--- a/doc/admin-guide-cloud/section_adding-images.xml
+++ b/doc/admin-guide-cloud/section_adding-images.xml
@@ -274,13 +274,17 @@
               <varlistentry>
                 <term>auto_disk_config</term>
                 <listitem>
-                  <para>A boolean option. If true, the root partition
+                  <para>If true, the root partition
                     on the disk is automatically resized before
                     the instance boots. This value is only taken into
                     account by the Compute service when using a
                     Xen-based hypervisor with the XenAPI driver. The
                     Compute service tries to resize a single partition
-                    in ext3 or ext4 format is on the image.</para>
+                    in ext3 or ext4 format is on the image.
+                    To specify that an image's disk cannot be resized
+                    add <literal>auto_disk_config=disabled</literal> as
+                    an image property with <command>glance image-update</command>
+                    .</para>
                 </listitem>
               </varlistentry>
               <varlistentry>
diff --git a/doc/image-guide/ch_openstack_images.xml b/doc/image-guide/ch_openstack_images.xml
index 734d0a7d94..787f21fe94 100644
--- a/doc/image-guide/ch_openstack_images.xml
+++ b/doc/image-guide/ch_openstack_images.xml
@@ -55,8 +55,8 @@
                 automatically adjust the partition and filesystem for your instance on boot.
                 Automatic resize will occur if the following are all true:<itemizedlist>
                     <listitem>
-                        <para><literal>auto_disk_config=True</literal> in
-                                <filename>nova.conf</filename>.</para>
+                        <para><literal>auto_disk_config=True</literal> is
+                         set as a property on the image in the Image Registry.</para>
                     </listitem>
                     <listitem>
                         <para>The disk on the image has only one partition.</para>