| 134 | | Note: the above assumes that the Nagios server is configured to collect performance metrics. |
| | 134 | Note: the above assumes that the Nagios server is configured to collect performance metrics. The default Nagios master template `monitoring/nagios/master` contains the required definitions. |
| | 135 | |
| | 136 | |
| | 137 | == Passive service checks (NSCA) == |
| | 138 | |
| | 139 | Besides displaying results or sending notifications for regular checks, Nagios can also receive results from checks that it did not initiate itself. Such checks are passive checks. They are executed via some mechanism external to the Nagios server (e.g., a cron job on a node) and the check result is sent to the NSCA daemon that runs on the Nagios server. On the node, the send_nsca executable submits the results to the NSCA daemon. The NSCA daemon accepts the passive check results and inserts them into Nagios. |
| | 140 | |
| | 141 | Passive service checks are required when using a hierarchy of Nagios servers. The slave servers that execute the (active) service checks, submit the check results to the master server. |
| | 142 | |
| | 143 | There are 3 different configuration variables to enable parts the NSCA configuration: |
| | 144 | A `NSCA_SEND_TEMPLATE`: required for nodes that run passive checks and slave servers to submit check results to the master |
| | 145 | A `NSCA_SUBMIT_RESULT_TEMPLATE`: required for Nagios slave servers to submit check results to the master |
| | 146 | A `NSCA_DAEMON_TEMPLATE`: |
| | 147 | |
| | 148 | == Hierarchy of servers == |
| | 149 | |
| | 150 | |
