Determining the Correct FlexNet Hostid


How can I determine the correct FlexNet hostid for my new Synopsys license server?

For a given OS / hardware platform, there are multiple ways to determine the hostid. However, not all methods are valid with the FlexNet licensing scheme implemented by Synopsys.

Normally, you determine the hostid for your license server with the lmhostid utility included with Synopsys Common Licensing. However, if you need to determine the hostid for a system that does not have SCL installed, where possible, an alternative method is provided below.

NOTE:  For SCL download information, see

Determine your hostid by using one of the following methods:


lmhostid Method - Physical Machines or Non-Cloud VMs

To determine the hostid, go to the command prompt and use the lmhostid command included with SCL.  The result will be a 12-alphanumeric hostid.  For example,

% cd scl_root/linux64/bin  # (or cd scl_root\win32\bin)
% lmhostid
 lmhostid - 1989-2019 Flexera. All Rights Reserved.
The FLEXlm host ID of this machine is "001125c4a904"

Note: If more than one hostid is listed, any hostid may be used. However, for non-VM machines, the hostid should correspond to a physical device such as an ethernet card or ethernet chip embedded on the motherboard.

lmhostid Method - Cloud VMs

  • Start the FNLS Service for the Cloud
    Before running lmhostid, you must start the FlexNet Publisher Licensing Service as a root or administrative user.  The FNLS installation executable is included with SCL in the scl_root/platform/bin directory. 
  • For Linux, run "sudo install_fnp --cert". 
  • For Windows, go to the Windows Powershell (admin) prompt and run
    "installanchorservice snpslmd all".
  • Now open a shell (command prompt) and type
  • lmhostid -ptype VM -uuid  # All Supported Clouds
  • lmhostid -ptype AMZN -eip  # Amazon AWS Only


  • All Clouds
    % lmhostid -ptype VM  -uuid
    % lmhostid - Copyright (c) 1989-2019 Flexera.  All Rights Reserved.
    The FlexNet host ID of this machine is "VM_UUID=42122EC8-299B-FAB0-43EA-3AF23BDA6D57"
  • AWS only
    % lmhostid -ptype AMZN  -eip
    % lmhostid - Copyright (c) 1989-2019 Flexera.  All Rights Reserved.
    The FlexNet host ID of this machine is "AMZN_EIP="

For more details on setting up SCL for cloud servers, see the cloud chapter of the SCL Administration Guide, which is included with SCL in the doc subdirectory.


lmhostid Method -Dongle-based licenses

Dongle-based licenses are supported:

  • for specific tools only (for example, HSPICE or Synplify Pro)
  • on Windows and Linux x86_64 platforms only
  • on physical mahines (dongle-based licenses should not be used on virtual machines)

If you have a dongle, the hostid is written on the device, which attaches to the USB port.
To determine whether the dongle hostid is correctly detected, enter lmhostid -flexid.
For example,
C:\> cd C:\Synopsys\SCL\2021.12\win32\bin
C:\Synopsys\SCL\2021.12\win32\bin> lmhostid -flexid 
lmhostid - Copyright (c) 1989-2019 Flexera. All Rights Reserved.

The FLEXlm host ID of this machine is "FLEXID=10-0BED15A7"

Note: If the dongle is not recognized, install the latest dongle driver included with SCL.  For the Windows OS, the FLEXID9 and FLEXID10 drivers are located at scl_root\win32\drivers.  


Other Methods

In addition to lmhostid, the following platform-specific methods of determining a hostid are supported. For the methods that involve quotes, be sure to use backquotes ( ` ) and not regular quotes.


The Linux "hostid" command produces a 6- or 8-character result that is not valid as a Synopsys hostid.
Instead, get the 12-character ethernet address. For example: 

% /sbin/ifconfig -a | grep -i ether
The result might be:
ether 00:06:5B:82:F4:5A  txqueuelen 1000  (Ethernet)
>> In this example, the hostid is 00065B82F45A

Note:  If more than one hostid is returned, consider choosing the last hostid on the list, which usually corresponds to the ethernext device eth0, em1, en1, or similar.


To determine the hostid needed for

  • networked (floating) licenses -OR-
  • nodelocked licenses tied to an ethernet address—
    use the MAC address of your ethernet device:
  1. Click Start-Run and type "cmd"
  2. Type ipconfig /all  (or ipconfig /all  | more)
  3. Look for the Ethernet adapter "Physical Address"  


Ethernet adapter Local Area Connection:

Connection-specific DNS Suffix:
Description . . . . . . . . . : 3Com 3C920 Fast Ethernet
Physical Address. . . . . . . : 00-06-5A-21-95-44

>> In this example, the Synopsys hostid is 00065A219544

For Amazon AWS, you may use the Elastic IP address (for example, "AMZN_EIP=")

For other clouds (such as Microsoft Azure or Google Cloud Platform), you will need the VM_UUID

It is not recommended that you use a utility such as dmidecode to determine the VM_UUID, as this is not reliable.  (For instance, on Azure, you would need to reorder the dmidecode output.)  Instead, you should install the FlexNet Licensing Service included with SCL (for Linux, sudo --cert), then run the below command:

% lmhostid -ptype VM -uuid  # For the VM_UUID hostid

For more information on Cloud setup, including installing the FlexNet Licensing Service, see the cloud chapter of the SCL Administration Guide.