diff --git a/docs/admin-guide/configuration/software/pmodules.md b/docs/admin-guide/configuration/software/pmodules.md
index f594c59e..51b19bd4 100644
--- a/docs/admin-guide/configuration/software/pmodules.md
+++ b/docs/admin-guide/configuration/software/pmodules.md
@@ -1,5 +1,8 @@
 # PModules
 
+!!! warning
+    Although this guide shows how to configure PModules on RHEL9, PModules with AFS backend is not supported on RHEL9!
+
 This guide describes how to configure PModules on RHEL9 via hiera.
 More details about Pmodules can be found here: https://gitea.psi.ch/Pmodules/