You will have to contact the Business Center to transfer your license to the new license server.
A network license is tied to the Ethernet address (aka MAC address or physical address) of a network adapter on the license server computer. So you need a new license if you move your license server to a different computer.
After you set up the new license server, update the setenv.bat files on your workstations to point to the new license server.
Note that on the workstations, the location of the old license server persists in the registry value HKEY_CURRENT_USER\Software\FLEXlm License Manager\ADSKFLEX_LICENSE_FILE. It’s a good idea to clear that value, to make sure XSI.exe and xsibatch.exe don’t try to use the old server.