Detecting Online/Offline Devices & Creating Rule

[user2699]

I’m looking for a way to detect that a device like a light or outlet is online/offline and if it is, turn another device on/off?

[bravenel]

@user2699

I’m looking for a way to detect that a device like a light or outlet is online/offline

In general, this won't be possible. The hub is event driven, and there is no event for a device going offline. After the fact, it can be determined that a given device has not reported in some amount of time when a report would likely have happened. But any attempt to do this in real time is bound to fail one way or another.

[HAL9000]

There are user-written apps than can report on devices that should report in periodically (e.g., battery reports) but have not. Have a look here:

Is there a definitive and reliable way to actively monitor devices going down?

This is most essential with security related application. I've been deploying 433Mhz alarm panels for many years and the issue is not being able to catch the sensors going down (broken or battery issue) right away which poses a security concern. Thus, I need a way to make sure that I am alerted if a sensor goes offline (specially door, motion, and other sensors). The alerting part can be a sound or TTS speak command, or whatever works. But it's the monitoring part that seems to be the challenge…