diff --git a/environments/common/inventory/group_vars/all/defaults.yml b/environments/common/inventory/group_vars/all/defaults.yml
index 23448c80d..91db4dc3a 100644
--- a/environments/common/inventory/group_vars/all/defaults.yml
+++ b/environments/common/inventory/group_vars/all/defaults.yml
@@ -58,6 +58,7 @@ appliances_local_users_default:
         uid: 981
         home: "{{ prometheus_db_dir }}"
         shell: /usr/sbin/nologin
+        system: true
       enable: "{{ 'prometheus' in group_names }}"
     
     - group:
@@ -69,6 +70,7 @@ appliances_local_users_default:
         uid: 984
         home: /usr/share/grafana
         shell: /sbin/nologin
+        system: true
       enable: "{{ 'grafana' in group_names }}"
 
 # Overide this to add extra users whilst keeping the defaults.