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The configuration is the realm scheduler list where the poller will have to connect.
DMZ Poller
It's possible to set poller in a DMZ zone, and the schedulers into the LAN. In this situation, the goal is to avoid DMZ (poller) to LAN (schedulers) connexions. In this case, it's possible to set the poller as passive. In this case, the scheduler will open a connexion to the poller.
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Only checks for host in this DMZ will be launched by this poller.
Data
The poller get command from the schedulers.
It's important to note that the plugins launched by the pollers will have a direct access to the monitored hosts, and they will need to get data from them.
Poller Internals
Poller connexions summary
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