diff --git a/ohpc-instance/main.tf b/ohpc-instance/main.tf
index 7c2ce2877d0fb29fc201c6f7ebeb39905d6d156d..f29dac9429501036e3d255fa4fa94c1e1f6d6682 100644
--- a/ohpc-instance/main.tf
+++ b/ohpc-instance/main.tf
@@ -78,12 +78,12 @@ resource "openstack_compute_floatingip_associate_v2" "ohpc" {
 # Attach specific volumes
 resource "openstack_compute_volume_attach_v2" "attach_prod_volume" {
   instance_id = openstack_compute_instance_v2.ohpc.id
-  volume_id   = var.data_volume
+  volume_id   = data_volume
 }
 
 resource "openstack_compute_volume_attach_v2" "attach_prod_queue_volume" {
   instance_id = openstack_compute_instance_v2.ohpc.id
-  volume_id   = var.prod_volume_id
+  volume_id   = prod_volume_id
 }