https://stackoverflow.com/questions/2332741/what-is-the-theoretical-maximum-number-of-open-tcp-connections-that-a-modern-lin specifies a theoretical maximum of 65,535 per user per server port, but a better method to determine your maximum is to find your maximum number of file descriptors for every socket connection must have one. The configuration can be altered with sysctl, but the ceiling is normally over 300,000.