Nagios, 2nd Edition

5.5 The Nagios Service Check Acceptor

The fifth method of processing the results of service checks leads to the use of the Nagios Service Check Acceptor, NSCA. This runs as a daemon on the Nagios server and waits for incoming test results (see Figure 5-1 in the right in Chapter 5). This method is referred to as passive, because Nagios itself does not take the initiative.

NSCA uses the interface for external commands used by CGI scripts, among others, to send commands to Nagios. It consists of a named pipe^[48] from which Nagios reads the external commands. With the command PROCESS_SERVICE_CHECK_RESULT Nagios processes test results that were determined elsewhere. The interface itself is described in more detail in 13.1 The Interface for External ...