The port numbers that are assigned for binds that specify port number 0 and IP address INADDR_ANY are reserved for use in z/OS UNIX. They are specified on the INADDRANYPORT and INET in the parmlib member used to start z/OS UNIX. You must increase the number of ports available either by specifying the INADDRANYCOUNT operand (if it was not specified), or by specifying a larger number for that parameter. Make sure that you also specify that same larger number on each of the transport providers. After changing these values, you must reIPL your system in order for the new numbers to take effect.