Opening and running Ansys Lumerical CAD or simulation requires a consistent connectivity with the license server (except for borrowed license). This article will explain how this connectivity works and what happens when the connection to the license server is lost.
Lumerical CAD/GUI behavior
Every ~5-10 minutes, the CAD/GUI checks-in with the server. This is called the 'heartbeat'. When it can't connect to the license server, the following process occurs:
- An error message will be shown that the connection to the license server is lost.
- The CAD/GUI will try to reconnect with the license server and displays the error message with a countdown on when it will timeout and lose the license.
- The CAD continues to operate as normal after 60 minutes, at which point this will time out and you will not be able to use the CAD. It will now be in 'read-only' mode, e.g. saving or editing is not possible.
- If connection is restored after the time out, the CAD will resume full functionality and indicate that the connection to the license server has been restored.
Lumerical simulation behavior
- Running the simulation while the client machine loses connection to the license server will stop the simulation with a licensing error.
Losing and restoring connection to the server
- By default, after ~2-2.5 hours, if the license server does not receive any communication (heartbeat) from the client machine that checked out the license, it will release and check in all licenses that were checked out by the client machine. These licenses will now be available for checkout.
- Once the client machine restores connection to the server, it will check out a new license, it will not be using the previous license it checked out prior to losing the connection to the license server.
- The previous license that is left in the check out state due to network connectivity is now an 'abandoned license'.
- If the license is not released or checked back in, it's referred to as a 'stuck license'. See 'How to release a stuck license' for more information.