I am using icinga2 for monitoring, and I want to include devices like NVR's located at customer sites. These cannot be pinged to check the host state.
The Icinga2 agent reports everything I need just fine without needing to forward certain ports.
However the host state itself is always 'DOWN' because this is checked using ping. I would need the host to only be considered 'DOWN' if the agent hasn't reported anything in a timely manner. For now I am checking on the HTTPS website that the NVR exposes, but that isn't exactly what I want since it could be possible that the NVR service is down but the device itself is up.