Ideally, the license server should be at the same point version as the keystrings you are serving.
It is not recommended to let the license server software version fall more than one major release behind.

For example, if you are serving 21.0 keystrings, it is ideal to have your license server version at 21.0. The minimum version should be the latest production build of Houdini 20.0.

Please check the system requirements to ensure your operating system is supported for Houdini licensing.

Upgrading the server software will not automatically upgrade your licenses. You will need to use the License Administrator or sesictrl to upgrade the installed licenses to the next version.

To upgrade your Houdini License Server software:

1. Download the latest Production or Daily build of the Houdini version you are looking to install.

2. Run the installer, ensuring to install the License Server component.

   • To upgrade sesinetd on Linux, you do have the option of installing only the license server sesinetd.
   • For Windows and OSX, ensure the License Server is checked. This will upgrade the existing sesinetd service or daemon.
     
     

3. During the installation process, the license server component will be automatically restarted. This should take only a minute.
   

If you are running a central license server, we do recommend alerting your users that an upgrade will take place. It will be important for them to save their files during this time as a precaution. In general, an upgrade of the license server software will not impact users.

Server heartbeat

With the Houdini license server version 20.5 and newer, once a license is checked out and the server cannot be reached, the session will hold onto that license for up to 14 days or until it regains a connection to the license server. Note if the Houdini session closes (crash, machine restart) and the server is still offline, a new license cannot be acquired. The 14 day license hold only works if the license has been checked prior to the server becoming unavailable.

With older license server versions (pre-20.5), the heartbeat is set for approximately 20 minutes. This means that if a client machine is not able to make contact with the central license server in that time, the active Houdini session will close. There will be no license holds.