diff --git a/documentation/ref-manual/ref-variables.xml b/documentation/ref-manual/ref-variables.xml
index f4490fab16..827b0cf0eb 100644
--- a/documentation/ref-manual/ref-variables.xml
+++ b/documentation/ref-manual/ref-variables.xml
@@ -7484,6 +7484,24 @@ recipes-graphics/xorg-font/font-alias_1.0.3.bb:PR = "${INC_PR}.3"
             </glossdef>
         </glossentry>
 
+        <glossentry id='var-TEST_SERVER_IP'><glossterm>TEST_SERVER_IP</glossterm>
+            <glossdef>
+                <para>
+                    The IP address of the build machine (host machine).
+                    This IP address is usually automatically detected.
+                    However, if detection fails, this variable needs to be set
+                    to the IP address of the build machine (i.e. where
+                    the build is taking place).
+                    <note>
+                        The <filename>TEST_SERVER_IP</filename> variable
+                        is only used for a small number of tests such as
+                        the "smart" test suite, which needs to download
+                        packages from <filename>DEPLOY_DIR/rpm</filename>.
+                    </note>
+                </para>
+            </glossdef>
+        </glossentry>
+
         <glossentry id='var-TEST_TARGET'><glossterm>TEST_TARGET</glossterm>
             <glossdef>
                 <para>