Houdini 18 New License Features FAQs

How do I set up License Server Chaining?

The license management system with the release of Houdini 18 will support a new license configuration called chaining. This configuration allows License Servers (sesinetd) to be chained together. This allows license servers to be broken up based on whatever specification you may have (i.e. license product type).

To set up this configuration list a set of license servers separated by a semi-colon instead of specifying a single sesinetd to connect to. The first sesinetd in the list will try to execute the command (i.e. checkout) if that fails for some reason (cannot connect, the command failed, etc.) then the next sesinetd is tried, then the next and so on. Make sure to place the connection list in quotes when specifying the list using "hserver -S". For example, hserver -S "sesinetd1;sesinetd2".

To use this configuration you need at least an 18.0 Houdini License Server (hserver). The sesinetd and Houdini version does not currently have any requirements for this configuration.

For more information: https://www.sidefx.com/docs/houdini/ref/utils/hserver.html#license-server-chaining

How can I setup Peak Usage Logging?

Important: The license server (sesinetd) must be version 20.0.682 for the peak usage logging to be accurate. Version 18.5.875 or higher (for Houdini 18.5) or 19.0.549 or higher (for Houdini 19.0) are available for peak usage logging but they may not be completely accurate.

The peak license usage log stores the maximum number of concurrent uses of a license token during a time interval. Time intervals are typically set to 1 hour each. You can inspect the contents of this log at any time.

This is a great option to monitor your peak license usage by product type. During a given interval the peak usage and optionally the users who used it are recorded to a binary log file. The log may be exported to less compact different representations such as spreadsheets or databases for analysis.

For detailed information, refer to Peak Usage Logging.

Enable usage logging

Peak license usage is enabled by default in the sesinetd.ini file, with the option to log every hour:


This will log the peak number of licenses used in the hour. To keep the log file compact, if no one has used the license in the interval then nothing is logged for that license.

To modify the various options for the license server sesinetd, edit or create the sesinetd.ini file.







There are additional intervals you may specify such as minute, 5-minute, 30-minute, 4-hour, 12-hour and day.

For example:

To log every 5 minutes without user information:


To log every minute with user information:


The includeUsers option logs who used the license within the time interval. By default only the peak usage for each license is logged without user information.

Make sure to choose the interval correctly as the smaller the interval the larger the log file and the longer the export will take.

Running sesinetd --print-options will show if peak usage logging has been enabled, the interval used and location of the log file.

An example on Linux:

 /usr/lib/sesi/sesinetd --print-options

 == Usage ==
 Peak Usage Enabled: true
 Usage Interval: hour
 Send usage interval: -1
 Include Users: false
 Usage File: '/usr/lib/sesi/sesinetd_peak_usage.bin'
 Usage Log URL: ''

The usage log file

The peak usage information is logged to a binary file.
There is a log file parser that is shipped with Houdini. The parser will allow the data to be exported to different representations.

The default location is in the license path with the name sesinetd_peak_usage.bin.

The peakUsageFile option specifies the custom location for the log file.

Mac default path:


Windows default path:


Linux default path:


Using the log file parser

Using hython, run $HFS/houdini/python.10libs/parsepeakuserlog.py for how to use the script. $HFS is the installation location of Houdini.

The xlsxwriter module is needed if you would like to use the xlsx export type.

For automatic time zone support, or to use the --time-zone option, you will need to install the ptyz Python module.
It will always show the times in the non-daylight savings time.

An example:

hython $HFS/houdini/python3.10libs/parsepeakuserlog.py /usr/lib/sesi/sesinetd_peak_usage.bin --group-by=hour

How can I set up HTTP communication support?

Houdini 18.0 adds http communication support to our licensing products. The biggest advantage this new communication protocol has is that its more resilient to modifications on either end of the communication. Http communication also allows users to query the license server using any language that can execute an http request (i.e. python). Houdini 18.0 License server (sesinted) already fully support http communication so there is no extra setup required for this application. The HoudiniServer (hserver) does not by default use http.

To enable http communication on the client side (hserver) add -C to the command line or add "enableHttp 1" to the HoudiniServers option file.

If you would like a more comprehensive diagnostic output from an 18.0 hserver then run "hserver -f -v". This command uses http to grab as much information as possible from the hserver.

Several new commands were added to sesictrl that use http communication. Run "sesictrl --help" to see a list of all available commands.