diff --git a/data/grid5000/sites/nancy/clusters/grat/grat.json b/data/grid5000/sites/nancy/clusters/grat/grat.json
index 46df66a2c1eee07e80eeab4193bcff14fce44063..9a292ba12dd96eaa0d22793cc99b03a04b75caf1 100644
--- a/data/grid5000/sites/nancy/clusters/grat/grat.json
+++ b/data/grid5000/sites/nancy/clusters/grat/grat.json
@@ -1,5 +1,5 @@
 {
-  "boot_type": "bios",
+  "boot_type": "uefi",
   "created_at": "Wed, 07 Sep 2022 00:00:00 GMT",
   "exotic": false,
   "kavlan": false,
diff --git a/input/grid5000/sites/nancy/clusters/grat/grat.yaml b/input/grid5000/sites/nancy/clusters/grat/grat.yaml
index 86ef028a0903a522b8912264e6d40fb6cefc90e1..ce9fb95f087807f0b046badb06cbc715eed56f06 100644
--- a/input/grid5000/sites/nancy/clusters/grat/grat.yaml
+++ b/input/grid5000/sites/nancy/clusters/grat/grat.yaml
@@ -1,7 +1,7 @@
 model: HPe Apollo 6500
 created_at: 2022-09-07
 kavlan: false
-boot_type: bios 
+boot_type: uefi
 exotic: false
 queues:
   - admin