diff --git a/docs.it4i/general/accessing-the-clusters/graphical-user-interface/ood.md b/docs.it4i/general/accessing-the-clusters/graphical-user-interface/ood.md
index b43bcc819f75ba70f19307e03c2dadb1a4b36587..630089a2438925f1d0754f376dc45d057665c500 100644
--- a/docs.it4i/general/accessing-the-clusters/graphical-user-interface/ood.md
+++ b/docs.it4i/general/accessing-the-clusters/graphical-user-interface/ood.md
@@ -9,6 +9,7 @@ For more information, see the [Open OnDemand][2] documentation.
 ## Access Open OnDemand
 
 To access the OOD interface, go to [https://ood.it4i.cz][3] and enter your e-INFRA CZ or IT4I credentials.
+Note that you must be connected to IT4I VPN to access the service.
 
 From the top menu bar, you can manage your files and jobs, access the cluster's shell and launch interactive apps on login nodes - Mate & XFCE desktops.