Starting a token server

Important note: most Gurobi licenses do not use the token server. You should only follow these instructions if you are setting up a floating license. If you are not sure whether you need to start a token server, you can examine the contents of your gurobi.lic file. If it contains the line TYPE=TOKEN then you need a token server, except if you also have the additional lines USELIMIT=1 and MACHINELIMIT=0.

On a Windows system, you can start the token service by selecting the Gurobi Token Server menu item from the Gurobi folder of the Start menu. You should only do so after you have installed the Gurobi license key file.

By default, the token server only produces logging output when it starts. To obtain more detailed logging information, start the token server with the -v switch. This will produce a log message each time a token is checked in or out.

The token server runs as a Windows service. If you'd like to run it in the foreground, start it from and command window and use the -n switch.


The next step after starting the Gurobi token server depends on your anti-virus software and firewall settings. Most anti-virus software will immediately ask you to confirm that you are allowing program grb_ts.exe to receive network traffic. Once you confirm this, the token server will start serving tokens. If you don't receive such a prompt, you will need to add grb_ts.exe to the firewall exceptions list. To do this, select Allow a program through Windows firewall under the Security area of the Control Panel (labeled Allow an app through Windows firewall in Windows 8).

Some machines have more restrictive firewalls that may require additional action. The Gurobi token server uses port 41954 by default. If you are unable to reach the token server after taking the steps described, you should ask your network administrator for more information on how to open the required port.

Starting and stopping the grb_ts Windows service

Once the token service has been started, you should see the grb_ts service listed in the Services tab of the Task Manager. To start or stop the service, click on the Services button at the bottom-right of the Services tab, and then right-click on the Gurobi Token Server item on this screen.

You can also start or stop the Gurobi Token Server service from a Console window with administrator privileges. Running grb_ts -h lists command-line options. Issuing a grb_ts -s command stops a running token server. If you are unfamiliar with running command-line commands on a Windows system, you can learn more here.

Add the line


to your gurobi.lic file to start the license service in verbose mode. Verbose mode produces a log message (in the Windows Event Log) each time a token is checked in or out.

Next steps

Clients of the token server also need simple license files. Your next step is to set up a client license.

Once your token server is running and you've set up a client license, you can move on to testing the license.

Once you've set up a client license, you can test the state of the token server at any time, as well as get a list of the clients that are currently using tokens, by typing gurobi_cl --tokens.

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