Attempts to connect to an IBM Rational License server, which is up and running with valid license files installed results in the error "FLEXlm error -15 cannot connect to license server".
After a Rational product is installed, attempting to connect to license server using the License Key Administrator results in the FLEXlm -15 error.
Note: The client machine is not behind a firewall.
Not specifying the default lmgrd port number of 27000 may result in the failure of the client to connect to license server, even if the client machine is not behind a firewall.
Resolving the problem
Specify the default lmgrd port number of 27000 as follows:
- Open the License Key Administrator
- Click Settings > Server Ports...
- Type 27000 in the Port for "lmgrd" field
- Click OK