Internet Connection lost - Hub never reconnects

Several times now I have noticed that when I lose internet connectivity, the hub never reconnects to the internet. All internet integrations are broken, the iOS app won't connect, etc. I have to power the hub off and back on to get it to reconnect. One annoying by-product is that time time drifts because the hub can't get to the NTP server and rules eventually trigger when they shouldn't.

Example: Last night around midnight, the internet went down. When the internet was restored, the hub didn't connect. My wife got up around 3:00 AM to go to the restroom and the motion rule, that is normally triggered during the day, turned on the bedroom lights, BAM !!! just what you want at 3:00 AM, bright lights in your face and scrambling to shut them off and the iPhone app won't connect. I got up and looked and the hub thought that it was 8:36 AM. I powered off the hub and back on and it connected to the internet and retrieved the correct time.

Day before yesterday similar behavior. We had a power failure. The hubs and local network are on UPS's but the internet provider's amplifiers down the line were off and the internet connection died. Same thing. No re-connection and time drift.

Had I been away from home and not able to reset the hub, I would be out of commission...

Two questions:

  1. Is there a way to wake up the hub and make it try to reconnect? Is there a rule that I can write?
  2. Can the local clock hold the time better when it loses connection to the NTP server? Can I connect to a local NTP server?

Great product but the reliability is being tainted by this problem...

Any help would be appreciated.

I had noticed the same issue with my C5 hub not reconnecting to the internet when it is offline for a while and requiring a reboot to get it to see an update is available or to be accessible via the cloud links.

I hadn't noticed the time drift, although that could be because I was setting the hub up for an environment that wouldn't have internet a lot of the time and it didn't have any automations setup yet. If the time drifts that badly without NTP access then the entire idea of local processing isn't going to work. I haven't brought that hub up in its final location yet so hopefully its internal clock is more reliable.

I too was surprised at the time drift that radical. I had read on here about owners having issues with time drift but I never dreamed that it affect it that bad. Nevertheless, the connectivity issue is definitely causing some heartburn.

I saw this as well this week when my ISP connection failed for a while. It's not something that happens often, but it really appears to have caused the hub some serious difficulty. Even simple local automations (motion sensor active -> light goes on) weren't running properly.

@mike.maxwell Mike, I am sure that you guys are very busy cooking up hot fixes from the last update but when you get a breath can you look at this? It seems to be an issue with others as well. The internet reconnect issue is the biggest problem. The clock is an issue but that's secondary, I'm not sure why the hub won't reconnect following reconnection of the internet service, It happened again last night and seems to be fairly consistent. Normally my internet connection is solid but they are doing maintenance lately and it has been up and down, mostly late at night. Any help would be appreciated.

What version are you on. We have found several causes and fixed them in 2.1.4 but obviously we can't test all circumstances.

I just upgraded to 2.1.4 this morning. I was at the latest release before that upgrade and I can't remember what the number was prior to update, If you fixed some reconnect related issues in 2.1.4, fingers crossed, maybe that helps. I will "cause" an internet outage later and see if it reconnects.

Patrick is there a way to set the NTP server for those instances where we want to run a hub offline to keep the clock synced with a Windows machine on our network or was the clock drift caused by something else that shouldn't be an issue in this case?

Thanks.

Not built in. I'm sure there are ways to redirect NTP traffic or update the time directly via the web action the hub uses to set time manually.

All clocks drift, some more than others, that's why NTP exists and why we allow updates via a browser button.

I am running AsusWRT-Merlin firmware on my Asus RT-AC86U router. In a recent Merlin firmware update, he added the ability to redirect all NTP requests directly to the router's built-in NTP time server. After doing this, and by having my HE hubs, router and network switches all on a small UPS, I have never had any time drift/clock updating issues. Of course, if my router gets rebooted, it still relies on the Internet NTP time servers! :wink:

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Is the NTP server(s) in HE hub an IP address or name?

I believe name. But not 100%

Here is some previous information regarding NTP... FWIW... :wink:

@ogiewon I was just trying to think of other ways to redirect NTP. Routers that can redirect NTP are harder to find than routers that can redirect a name. I have a pretty powerful configurable router. I can do lots of redirecting traffic, but I can't touch redirecting port 123 to a local time server. It is, however, really easy add an entry to something as simple as a host file.
That all presumes that the Hubitat hub is using DNS servers handed out by the local DHCP server, which it probably doesn't. Just a thought.

Or you could just fire up something to POST to /location/updateTime with a body of a valid date time in this format 23 Aug 2019 11:23:53

And viola, your time is now set to that.

That's all the sync from browser button does.

Simple offline time sync via a local POST url.

Can be done via Tasker on Android pretty easily.

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Very interesting idea!!! Is there also a way to read the current time or is that buried in the full html? This way we could create a script that reads the time and only updates it in case it is wrong..... Very simple bash/curl or NodeRed flow

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Thankful everyday for your recommendation on this every time I hear of NTP issues after updates come out.....

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Even if the hub is not using the DHCP supplied DNS server(s), some routers allow you trap the DNS requests and force them to use the DNS server of your choice. I remember doing this years ago to force all DNS traffic through OpenDNS when the kids were young...and I wanted to safeguard their web surfing.

Which version was there before 2.1.4? Was it 2.1.3.128?

I believe that it was 2.1.3.128