A network listener is a system task that listens on a given network port for incoming client connections, and creates one database management system task for each client connection. Adaptive Server creates one listener task for each network port on which Adaptive Server listens for incoming client connection requests. Initially, these ports consist of the master entries in the interfaces file.
The initial number of network listener tasks is equal to the number of master entries in the interfaces file. The maximum number of network listeners (including those created at start-up) is 32. For example, if there are two master entries in the interfaces file under the server name at startup, you can create 30 more listener tasks.
Each additional listener task that you create consumes resources equal to a user connection. So, after creating a network listener, Adaptive Server can accept one less user connection. The number of user connections configuration parameter includes both the number of network listeners and the number of additional listener ports.
The number of listener ports is determined at startup by the number of master entries in the interfaces file.
For more information about the interfaces file, see Chapter 1, “Overview of System Administration,” in the System Administration Guide: Volume 1.
