Documentation


Creating a token server client license

The purpose of a token server client license is quite simple: it tells the client where to find the Gurobi token server. You can create this file yourself (using a text editor like WordPad, for example). The client gurobi.lic file typically contains a single line of text:

TOKENSERVER=mymachine.mydomain.com
or:
TOKENSERVER=192.168.1.100
You should of course substitute the name or IP address of your token server in the example above.

If your token server was configured to use a non-default port, you'll also need a line that provides the port number:

PORT=46325

The client license file may also include four optional lines. A QUEUETIMEOUT line allows you to set a limit (in seconds) on how long a new Compute Server job will wait in queue before it gives up (and reports a JOB_REJECTED error). Any negative value will allow a job to sit in the Compute Server queue indefinitely.

An IDLETIMEOUT line allows you to set a limit on how long a Compute Server job can sit idle before the server kills the job (in seconds). A job is considered idle if the server is not currently performing an optimization and the client has not issued any additional commands. The default value will allow a job to sit idle indefinitely in all but a few circumstances. The first exception is the Gurobi Instant Cloud, where the default setting will automatically impose a 30 minute idle time limit (1800 seconds). If you are using an Instant Cloud pool, the actual value will be the maximum between this parameter value and the idle timeout defined by the pool. The second exception is any program that uses the Gurobi Python interface (including the Gurobi Interactive Shell). Such programs will also get a 30 minute idle time limit by default.

A SERVERTIMEOUT line allows you to specify the timeout (in seconds) in case the token server is unavailable. The default value is 30 seconds. If the client program is unable to contact the server for more than the specified amount of time, the client will quit with a network error.

A PASSWORD line allows you to connect to a password-protected token server (you'll need to get the password from the owner of the token server).

A more complex client token file might look like this:

TOKENSERVER=192.168.1.100
IDLETIMEOUT=60
QUEUETIMEOUT=120
SERVERTIMEOUT=10
PASSWORD=abcd1234

We strongly recommend that you place your client gurobi.lic file in a default location for your platform (either your home directory or c:\gurobi). Setting up a non-default location is error-prone and a frequent source of trouble. (If you still want to use a non-default location, please refer to the instructions that appeared earlier in this section).

If your client and the token server are both running on the same machine, they can share a single gurobi.lic file. You just need to add the following line to the gurobi.lic file you obtained from our website:

TOKENSERVER=localhost
The token server will ignore this line, and the client will ignore everything but this line. Your other option when both client and server are running on the same machine is to create a separate gurobi.lic file for the client, and to set the GRB_LICENSE_FILE environment variable to point to this file (following the earlier instructions for using a non-default license location).

Once your client license is in place, you can test the license. If you are unable to connect to the server, you'll need to make sure the server is installed and running. Please consult the instructions for starting a token server for more information.