FLEXlm works with NIS and DNS. However, some sites have broken NIS or DNS, which can cause FLEXlm to fail.
In version 5 of FLEXlm, NIS and DNS can be avoided to solve this problem. In particular, sometimes DNS is configured for a server that is not currently available (for example, a dial-up connection from a Windows system). If DNS is configured but the server is not available, FLEXlm will fail.
On Windows, if a license checkout takes three minutes and then fails, this is usually because the system is configured to use a dial-up DNS server that is not currently available. In this case, the solution is to disable DNS.
Finally, host names must not contain periods. These are not legal host names and do not work correctly with DNS. However, Windows systems allow you to define them.