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Regularly scheduled host checks are optional. If you set the check_interval option in your host definition to zero (0), Shinken will not perform checks of the hosts on a regular basis. It will, however, still perform on-demand checks of the host as needed for other parts of the monitoring logic.
On-demand checks are made when a service associated with the host changes state because Shinken needs to know whether the host has also changed state. Services that change state are often an indicator that the host may have also changed state. For example, if Shinken detects that the "HTTP" check associated with a host just changed from a CRITICAL to an OK state, it may indicate that the host just recovered from a reboot and is now back up and running.
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Dependencies and Checks
You can define :ref:`host execution dependencies <configobjects/hostdependency>` parents that prevent Shinken from checking the status of a host depending on the state of one or more other hosts. More information on dependencies can be found :ref:`here <advanced/dependencies>`on the depdency logic page.
Parallelization of Host Checks
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