Why Does VLM Checkout Multiple Licenses at a Time?

Updated Nov 5, 2020

Reported In


  • Volume License Manager

Issue Details

In the NI Volume License Manager (VLM) I have assigned permissions for two different software produts to the same user or computer. For example, the same user is assigned permissions to use LabVIEW Full Development System and LabVIEW Professional Development System.
When the license request is made from the client to the server it checks out a license for both development systems. 

Is this expected behaviour?
Is there any modification to the license file that can I make in order to prevent it?


This is an expected behavior: The VLM is designed to checkout the most fully-featured license that it can for the user/computer.
In the case of the example above upon launching LabVIEW on the client machine, if a license for LabVIEW Full Development System is found by the VLM, this license is checked-out and the VLM will continue to search for any more remaining licenses that may be more fully-featured. Ultimately, when the VLM finds the LabVIEW Professional license, this will also be checked-out.
The result is that at the end of this procedure VLM will check-out both the Full and Professional Development licenses for LabVIEW.

In order to workaround this behavior, the most fully-featured license must be sorted above the other licenses. This way, NI VLM won't be able to find a more fully-featured license than the one that has already been checked out. Resulting in a single license checkout.
To obtain this behaviour, it is necessary to edit the order the licenses are parsed by the server. This can be done by opening the license file with a text editor and modifying the sort keywords in the file.
All the software packages are given a numeric order by which they are sorted expressed by the sort parameter. The package with the smallest sort order number is evaluated first by the VLM. Therefore editing such parameter value changes the order the software packages are parsed by the VLM.

Refering to the previous example, in order to resolve the issue the license file sort parameters need to be re-ordered in order for LabVIEW Professional to be found before the LabVIEW Full by NI VLM. A possible resulting sort order should reflect similarly to the list shown below.

BEFORE (LabVIEW FDS found first by the VLM)

  • LabVIEW Full Development System: sort=3 
  • LabVIEW Professional Development System: sort=4 

AFTER (LabVIEW PDS found first by the VLM)

  • LabVIEW Full Development System: sort=4
  • LabVIEW Professional Development System: sort=3

With this edit the only time the VLM will checkout a FDS License is when no PDS licenses will be available. 

Additional Information

It is possible to modify the sort number without the need to contact NI.