diff --git a/scripts/upgrade b/scripts/upgrade
index 4b36be1d..85e290a1 100644
--- a/scripts/upgrade
+++ b/scripts/upgrade
@@ -27,6 +27,7 @@ db_user=$db_name
 db_pwd=$(ynh_app_setting_get --app=$app --key=db_pwd)
 app_key=$(ynh_app_setting_get --app=$app --key=app_key)
 phpversion=$(ynh_app_setting_get --app=$app --key=phpversion)
+redis_db=$(ynh_app_setting_get --app=$app --key=redis_db)
 
 fpm_footprint=$(ynh_app_setting_get --app=$app --key=fpm_footprint)
 fpm_usage=$(ynh_app_setting_get --app=$app --key=fpm_usage)
@@ -70,6 +71,12 @@ if [ -z "$fpm_usage" ]; then
 	ynh_app_setting_set --app=$app --key=fpm_usage --value=$fpm_usage
 fi
 
+# If redis_db doesn't exist, create it
+if [ -z "$redis_db" ]; then
+	redis_db=$(ynh_redis_get_free_db)
+	ynh_app_setting_set --app=$app --key=redis_db --value=$redis_db
+fi
+
 # If app_key doesn't exist, retrieve it
 if [ -z "$app_key" ]; then
 	ynh_script_progression --message="Retrieving app_key..."