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Use of External Licenses

It is possible (please contact the support team first) for users to install their own software and use their own license servers, e.g. FlexLM. The outbound IP addresses from ZIH systems are:

  • compute nodes: NAT via
  • login nodes:

The IT department of the external institute has to open the firewall for license communications (might be multiple ports) from ZIH systems and enable handing-out license to these IPs and login.

The user has to configure the software to use the correct license server. This can typically be done by environment variable or file.


If you are using software we have installed, but bring your own license key (e.g. commercial ANSYS), make sure that to substitute the environment variables we are using as default! (To verify this, run printenv|grep licserv and make sure that you dont' see entries refering to our ZIH license server.)