There are four main components that make up the NDO utilities:

1. NDOMOD Event Broker Module : The NDO utilities includes a Nagios event broker module (NDOMOD.O) that exports data from the Nagios daemon.Once the module has been loaded by the Nagios daemon, itcan access all of the data and logic present in the running Nagios process.The NDOMOD module has been DESIGNED to export configuration data, as well as information about various run time events that occur in the monitoring process, from the Nagios daemon. The module can send this data to a STANDARD FILE, a Unix domain socket, or a TCP socket.
2. LOG2NDO Utility : The LOG2NDO utility has been designed to allow you to IMPORT historical Nagios and NetSaint log files into a database VIA the NDO2DB daemon (described later). The utility works by sending historical log file data to a standard file, a Unix domain socket, or a TCP socket in a format the NDO2DB daemon understands. The NDO2DB daemon can then be used to process that output and store the historical log file information in a database.
3. FILE2SOCK Utility : The FILE2SOCK utility is quite simple. Its reads input from a standard file (or STDIN) and writes all of that data to either a Unix domain socket or TCP socket. The data that is read is not processed in any way before it is sent to the socket.
4. NDO2DB Daemon: The NDO2DB utility is designed to take the data output from the NDOMOD and LOG2NDO components and store it in a MySQL or PostgreSQL database.When it starts, the NDO2DB daemon creates either a TCP or Unix domain socket and waits for clients to connect. NDO2DB can run either as a standalone, multi-process daemon or under INETD (if using a TCP socket). Multiple clients can connect to the NDO2DB daemon’s socket and transmit data simultaneously. A separate NDO2DB process is spawned to handle each new client that connects. Data is read from each client and stored in a user-specified database for later retrieval and processing.

There are four main components that make up the NDO utilities: