Strange happenings. Thought I would share

Today I received a APC back-ups for my birthday. The wife got it for me, isn’t she great. Well anyway I shutdown the hub like I’m supposed to do and setup the UPS, and all is OK. So tonight the wife opens the back door and the lights didn’t come on. After a few expletive’s deleted I started my Sherlock Holmes routine. I checked to make sure the contact sensor was working and it was. Then I checked the logs and found that the sensor registered open but the rule didn’t run. Then I noticed that the time in the logs was about an hour and a half off. So I reset the time to browser time, opened the door and viola lights. Now I don’t know why the time was off but I suspect it had to do with the time the hub was shutdown. So if I was to learn some kind of lesson from all this it would be, if something doesn’t work check the time.

So, I am guessing that your router and cable modem are also plugged into the same UPS?

My hypothesis is that When the UPS was turned on, the Hubitat Hub started up quicker than your cable modem/router. Thus, when the Hubitat hub tried to update its time via NTP, it failed to access the internet, and thus its time was wrong. I believe the hub will eventually correct itself, however I am not sure how long this takes.

This is a well-known issue with the hub. Hopefully @gopher.ny will add this to the to-do list for a future update.

In the meantime, there is a community developed driver that can be used to uptime the hub’s time via NTP based on whatever logic you desire. Many use the hub’s system startup event in rule machine, to start a 10 minute delayed action to have the hub’s time updated.


Well no. The router, cable modem and switch are in a closet whereas the hub is centered in the house all by itself. The UPS installation only affected the hub.

Any chance you powered the Hubitat hub up with its Ethernet cable unplugged?


@ogiewon...there you go again providing really useful stuff. When are you going to learn that only results in more questions from me... :wink:

I can't find the "system startup event" to use in Rule Machine as the rule trigger. Can you point me to the promised land of automatic time updates? :slight_smile:

NVM - found it! Location event, system startup.

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Yes I did. Funny you should mention that. I mistakenly powered up the hub without the ethernet cable plugged in and then promptly plugged it in.


I have never, ever, ever made a dumb mistake like that.

At least not so far today, but there's still lots of time until midnight... :wink:

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Are you insinuating that I am dumb. I resemble that.



Thank you for a detailed description - the issue got my proper attention now and will get bumped up on the priority list.


Thank you!

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I will say "your welcome" for starting this thread. Action will commence.

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