Change tmpdir dir location /etc/one/sunstone-server.conf not working

We wanted to change the tmpdir from suntstone in the /etc/one/sunstone-server.conf because otherwise our root dir / will get to full when we upload a image

After we change the /etc/one/sunstone-server.conf from tmpdir: /var/tmp to tmpdir: /mnt/one/upload and restart the sunstone deamon (sudo systemctl status opennebula-sunstone.service).
We attempted to upload a qcow2 image with the sunstone web interface but then it downloaded the images to /tmp.

Is this the fallback default?

-folder permissions
drwxrwxrwx /mnt/one/uploads

OS ubunu 16.04
opennebula/xenial,now 5.4.1-1 amd64 [installed]
opennebula-common/xenial,xenial,now 5.4.1-1 all [installed,automatic]
opennebula-flow/xenial,xenial,now 5.4.1-1 all [installed]
opennebula-gate/xenial,xenial,now 5.4.1-1 all [installed]
opennebula-node/xenial,xenial,now 5.4.1-1 all [installed]
opennebula-sunstone/xenial,xenial,now 5.4.1-1 all [installed]
opennebula-tools/xenial,xenial,now 5.4.1-1 all [installed,automatic]
ruby-opennebula/xenial,xenial,now 5.4.1-1 all [installed,automatic]

-content of file:

Server Configuration

#Directory to store temp files when uploading images
:tmpdir: /mnt/one/uploads
#:tmpdir: /var/tmp

-Image upload parameters with sunstone:
type: OS
Image mapping driver: qcow2

|BRIDGE_LIST |kvm01 kvm02kvm03|
|CEPH_HOST |mon01 mon01 mon03|
|CEPH_SECRET |*********************|
|CEPH_USER |libvirt|
|DRIVER |raw|
|DS_MAD |ceph|
|POOL_NAME |one|
SAFE_DIRS /var/tmp /mnt/one/uploads
STAGING_DIR /mnt/one/uploads
|TM_MAD |ceph|