MQe uses TCP/IP sockets for communications and files to hold messages in persistent storage. On a system where a large number of messages are being flowed or a large number of clients are connecting (or both), operating system limits may be encountered. To ensure this does not cause a problem, the system administrator should ensure there will be enough file descriptors and TCP/IP sockets available. The method for doing this varies between operating systems. See the operating system documentation on how to set these limits.