diff --git a/nixos/doc/manual/installation.xml b/nixos/doc/manual/installation.xml
index 6ccb12b115e7..f6b477ed69bc 100644
--- a/nixos/doc/manual/installation.xml
+++ b/nixos/doc/manual/installation.xml
@@ -1,5 +1,6 @@
 <chapter xmlns="http://docbook.org/ns/docbook"
-         xmlns:xlink="http://www.w3.org/1999/xlink">
+         xmlns:xlink="http://www.w3.org/1999/xlink"
+         xml:id="installing-nixos">
 
 <title>Installing NixOS</title>