Please note that during the SARS-CoV-2 pandemic, we have been updating our academic license validation rules when restrictions limited access to university campuses. We recently returned to our previous validation rules requiring users to be on an academic network to validate their licenses, so you may encounter this error when you didn't previously.
While setting up an academic license file via grbgetkey, you may receive the following error message:
error : ERROR 303: hostname <host> (<IP address>) not recognized as belonging to an academic domain
info : Is your computer connected to the university network?
info : Your computer must be connected to the university network for the grbgetkey
info : command to work. You can connect your computer either directly or via a VPN
info : that tunnels all traffic through the university network. Once the license
info : file is setup, your computer does not need to be connected to the university
info : network. You can repeat this process to get licenses for additional computers.
info : If you are unable to setup this license file, please visit our support website
info : https://support.gurobi.com for further assistance.
This error means your domain isn't on our academic domain list. To resolve this issue, please try the following:
- Make sure you are connected to your university network. If your university provides a VPN, connect to it before running grbgetkey.
- Some VPNs are configured to use split tunneling, where traffic to public internet sites is routed through your ISP. If possible, try configuring your VPN client to use full tunneling, where all traffic is routed through the VPN. Alternatively, ask your network administrator if the VPN can be configured to route traffic to gurobi.com through the private network.
- If traffic gets split via split tunneling and not all your internet traffic is directed through the VPN connection, you can try to force the traffic to not be split.
If you are still receiving the 303 error, please submit a new support request, attach a screenshot of the error, and indicate that you already tried the suggestions discussed above to no avail.
- Quick Start Guide > Academic validation (Windows, Linux, MacOS)
- How do I install Gurobi on a machine without internet access?
- How do I resolve the error "grbgetkey: command not found"?
- How do I resolve an "ERROR 405" from grbgetkey?
- How do I resolve the error "Communication failed" from grbgetkey?