Access NI Volume License Manager from a Different Network or Behind a Firewall

Updated Apr 20, 2023



  • Volume License Manager
  • License Manager

Operating System

  • Windows

My company uses NI VLM (Volume License Manager) to manage our NI software licenses. I know that I should install NI VLM on a server computer that is accessible by most computers, but my server is on a different network or behind a firewall. How can I configure NI VLM so that my clients can check out permissions from the server?

To supply licenses for clients on more than one network, different subnets, or when the server is behind a firewall, you have the following options:
Try connecting to your server using its IP and Port Number
If using the server's name is not letting you checkout and manage your licenses correctly, you can also point the NI License Manager to the correct port to use with your server following the guide located in: Testing NI License Manager Volume Licensing Configuration and Connectivity Refer to the second section of the guide ("Configuration and Connectivity") to learn more troubleshooting steps you can try.
Configure your firewall to allow access
  • Configure the licensing daemons used by NI VLM to communicate over the Windows Firewall by completing the following steps:
  1. Go to Start»Control Panel»Windows Firewall.
  2. Change to the Exceptions tab. 
  3. Click the Add Program button. 
  4. Click the Browse button.
  5. Browse to the program found at C:\Program Files\National Instruments\Shared\License Manager\Bin\lmgrd.exe and click Open.
  6. Browse to the program found at C:\Program Files\National Instruments\Shared\License Manager\Bin\nilm.exe and click Open.
  7. Click OK twice to close the Windows Firewall setting dialog box. 
  • Open all the ports that are required for NI Volume License Manager and the client computers to communicate with each other. Find the most recent copy of your license file to set which ports will be used by editing the first two lines. The format is as follows:
SERVER <servername> <MAC address or Disk Volume Serial Number> <lmgrd port number>
VENDOR nilm PORT=<nilm port number>

You can change the nilm port number by modifying the line in your license file to resemble the above example. If you do not specify a nilm port number, the port will be chosen randomly. See the Related Links below for more information on editing the lmgrd port number. Do not use the same port number for nilm and lmgrd. Once you edit and save the license file, open NI Volume License Manager and install the edited license file and click Apply Changes.
Once you have set the ports, you need to allow communication over those ports through the Windows Firewall:
  1. Go to Start»Control Panel»Windows Firewall
  2. Change to the Exceptions tab. 
  3. Click the Add Port button. 
  4. Enter a name to represent the port and enter the port number. 
  5. Click OK.
Repeat these steps to add the second port to the list of exceptions. 

If you are not using the default Windows Firewall, consult your firewall's documentation for information on how to set these configuration options.

Disable your firewall
By navigating to Control Panel\All Control Panel Items\Windows Defender Firewall\Customize Settings and setting all the displayed options to Off.

Use disconnected licenses 
Disconnected licenses allow you to create a license file that contains all of the permissions necessary to use NI software without ever requiring that the client computer connect to the NI VLM server. For information on how to create disconnected licenses, see the NI VLM help or the document: Getting Started with NI VLM: Creating a Disconnected or Home License.

Use a VPN connection to access the network
If the network with the License Server has a VPN set up, you can use the VPN to access the network. The License Server should then be visible as if you are on the network. For information on setting up a VPN connection, contact your company's IT support personnel.

Check the server name in your license file
If you verified that the ports your license manager uses are open using telnet and still cannot connect to your VLM, you might need to change the server name to the fully qualified domain name. Contact with the name of the server and the name of the domain to get a new license file.

Use separate contracts 
If your networks cannot be configured to communicate with each other, you can split your Volume License contract into 2 or more sub-contracts. This would require you to install NI VLM on a server that is accessible by each of the client computers on each of the networks. If this solution fits your needs, please contact

Additional Information

Be aware that this method will ONLY work if you are trying to access your Volume License Server from a network that is immediately accessible from the network that the Volume License Server is on. This method will not allow you to check out licenses from the internet. If this functionality is required, you must set up either a VPN or use disconnected licenses.

For information on configuring your network, contact your company's IT support personnel.