License Check

There are two types of licenses used by Carbon in Houdini: the interactive (UI) license and the non-interactive (Batch) license.

When using floating licenses through a dedicated license server, it can be useful to understand the differences between these two types of license.

UI License

The Carbon interactive licenses are the less greedy of the two type of licenses, and are checked out per machine allowing you to run simultaneously multiple sessions on one machine without requiring additional licenses.

Note

This type of license can also allow the Carbon simulation to run in non-interactive sessions, but only if the environment variable NUMERION_FARM_UI_LICENSE is not set, or is set to any value other than 0.

The license is only checked out when a Carbon Simulation node is present. This could happen at its creation or when a scene containing such a node is loaded.

When no interactive license is available, the Carbon Simulation node will then fail to compute and have an error message similar to the following message:

Warning: Carbon failed to find a valid license in the following locations: C:\Users\UserName\Documents\numerion;
Carbon license checkout failed. Error code: 9
No Carbon license available. Please contact support@numerion-software.com to add/renew/install your licenses.

Please share this information when contacting support@numerion-software.com about license issues.

Batch License

The Carbon batch licenses are checked out per process, therefore two different non-interactive Houdini sessions running on the same machine will require two Carbon batch licenses.

Note

Loading a Houdini scene containing multiple Carbon Simulation nodes will still only use one license as both Carbon simulations will run within the same process.

When a non-interactive Houdini session runs a Carbon simulation (through hbatch or hython for example), batch licenses are always used first in preference to UI licenses. When no Carbon batch licenses are available, the Carbon simulation will then look for a Carbon UI license and use one if there is one available, but only if the environment variable NUMERION_FARM_UI_LICENSE is not set, or is set to any value other than 0.

NUMERION_FARM_UI_LICENSE is not set, or is set to any value other than 0

Running a Carbon simulation using hython or hbatch when no Carbon licenses are available will lead to warnings/error messages similar to this:

Warning: Carbon failed to find a valid license in the following locations:
C:\Users\sebastian\Documents\numerion;
Carbon license checkout failed. Error code: 9
No Carbon Batch license available. Trying Carbon UI license instead.
Warning: Carbon failed to find a valid license in the following locations:
C:\Users\sebastian\Documents\numerion;
Carbon license checkout failed. Error code: 9
Warning: Carbon failed to find a valid license in the following locations:
C:\Users\sebastian\Documents\numerion;
Carbon license checkout failed. Error code: 9
No Carbon license available. Please contact support@numerion-software.com to add/renew/install your licenses.

NUMERION_FARM_UI_LICENSE is set to 0

Running a Carbon simulation using hython or hbatch when no Carbon licenses are available will trigger this python exception on the first frame of the simulation:

Warning: Carbon failed to find a valid license in the following locations:
C:\Users\sebastian\Documents\numerion;
Carbon license checkout failed. Error code: 9
No Carbon Batch license available and NUMERION_FARM_UI_LICENSE set to 0.
No Carbon license available. Please contact support@numerion-software.com to add/renew/install your licenses.

Automatic Check-in

After two hours of inactivity from the Carbon Solver (no cook on the Carbon Simulation node), all licenses will get automatically returned.

Note

If after that the Carbon simulation is re-started, it could fail if all licenses have been taken by other users in the meantime.