Nagios 3.0 presents a series of improvements and innovations compared to the 2.x versions.. Much of this is not noticeable from the outside, and the configuration is also nearly identical; normally Nagios 3.0 will also start with a functioning Nagios-2.x configuration. None of the new configuration parameters are absolutely essential.
Some parameters were renamed, and Nagios 3.0 complains on startup that a parameter contained in the configuration has been removed, then sets the new variable to a sensible value. The objects
service-extinfo are considered to be obsolete, but can still be used, at least in version 3.0.
Apart from the configuration, the internal logic has been improved in many ...