Most people don’t have the IPv6 version of the Autodesk Network License Manager (NLM), because the IPv4 is installed by default.
To check if you have the IPv6 version, start LMTOOLs and go to the System Settings tab. If you have the IPv6 version, you’ll see an IPv6 IP address like fe80::252d:8892:22e8:34d6. If you have the IPv4 NLM, you’ll see a regular IP address like 10.123.456.78.
You can download the IPv6 NLM from autodesk.com/softimage-support.
Sometimes running the IPv4 NLM in an IPv6 environment will work, sometimes it won’t. Other times, you may have intermittent problems. I don’t do so many licensing cases anymore, but checking IPv6 was always on my list of things to check.
Just the other day, a customer reported that his render nodes could no longer get licenses. It turned out that after some recent updates, IPv6 was enabled and that was the cause of the problem. Installing the IPv6 NLM (or disabling IPv6) was the solution.
hat tip: my colleague David Lau from the Up and Ready blog