If I program up a spare hub and install it at my cousins home I know it can control devices via Zwave and Zigbee, but what if I want it to do a periodic reboot. How can I program that? Or, if there is a power failure will the hub reboot itself without a router or internet?
Rebooting a hub programmatically is pretty simple. Here is a RM rule that’ll do it.
As for rebooting without an Internet connection, the #1 issue is that the hub’s date/time will be incorrect. Time-based schedules will not fire at the correct time. There some solutions for this, but they involve the need to a local, accurate NTP time server to be on the same LAN as the Hubitat hub.
Also, it seems to me like you should still install a router, even if your cousin has no internet connection. How else would anyone ever connect to the Hub to configure/manage it? Typically, the hub gets its IP address from a DHCP server, usually provided by a home router.
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You should be able to pick up a suitable router inexpensively. If you have a Goodwill or other second hand store, you can probably get an used router (something like a WiFi4 (N) router for very little. Amazon sells a Archer/TP-Link N router for $25 (50% off currently). If you want something a little faster, you can get a low end WiFi5 (AC) router for just a few dollars more. If you ask around, you can probably get one for free.
You could connect directly to the Hubitat by using a computer, but then it has to be set up to assign IP addresses. You can do that, but an inexpensive router will accomplish that more easily. Then you can reserve a specific IP address for the Hubitat and any other LAN devices such as a Hue bridge. A WiFI router would allow you to use other WiFI devices such as smart assistants, WiFi plugs, etc.
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Thanks for the advice fellows. I had thought that perhaps a standalone hub wasn't going to be possible. I just tried disconnecting my C5 from the router and power. Then applied power and I could not control my test Zwave device at all. Not only that, my simple rule didn't run. So I guess the whole idea is down the drain unless I use a router. I'm sure I have an old Linksys router laying around which I could use.
Curious - how were you controlling your zwave device? From the web interface or a zwave switch? Obviously without a router you can't reach the hub to control the device, but if you have a preconfigured zwave switch and appropriate rule it should work just fine. Of course if things go wrong you will have exactly zero chance of diagnosing and fixing the problem then.
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I had a simple Rule that at x:xx time to repeat cycle the zwave switch. The hub had plenty of time to boot up and be ready when the time arrived. I was hoping the date/time would carry forward on a cold boot, but perhaps not. So the only alternative for me would be to take a laptop to the location of the hub and connect thru a router and get the hub running. Then if there is a power blip I'm sunk, unless I also put a ups on the router or at least the hub.
A time schedule requires the clock to be set. As you mentioned a reboot without internet access will mean the the onboard clock will not be updated correctly. Otherwise you will still need to access the hub through its web interface to manually set the time.
Well you could get a talentcell battery pack (search the forums here - they are available on amazon) and set up your hub at home with the battery connected and simply bring the whole setup there and hook the battery up to mains.
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A bit cumbersome but....
If you dedicated a contact switch (or a button) you could use it to set the time. Probably only to the nearest hour.
One thing you would want to do is set a static IP on the hub itself (make sure you change the DNS to 1.1.1.1). That at least would ensure the hub comes up on the local network cleanly instead of looking for the DHCP server (local router) If you want you can get an rpi and set up an NTP server on it and have the hub get it's time from that.
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Of course, the RPi needs an NTP server as well, in order for it to maintain accurate time. A GPS radio can be fitted to a RPi in order to maintain accurate time, or possibly an add-on RTC module with battery backup.
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I was just thinking there is less drift with the rpi so it likely would be ok for a couple of days should the internet be out that long.
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That depends on whether the HE has its own RTC or relies solely on the internal clock + regular NTP syncs.
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HE does not have an onboard battery backed up RTC. It relies on NTP server time syncs exclusively.
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The OP is talking about a location that has no internet access whatsoever.
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Ahh I misread.
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Still could be doable if the cousin sets the clock once a week on the rpi...
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AFAIK RTCs do not have to be battery backed (although they often are) hence the question. Wasn't sure if actually has an RTC chip on board.
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I don't believe the RPi has a battery to keep it's own time alive if it has a power interruption. Of course, with a network connection or GPS input it can reset itself. There is a small daughter board that will accept a battery and keep it alive. The Pi could also run DHCP (but static sounds simpler).
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Assuming your cousin's place is within reach of GPS, I'll repeat my recommendation for the TimeMachines TM1000A. It's pricey, but it just works, with no huhu.
As others have suggested, whatever external NTP source you use, you'll need a router to connect it to your Hub.
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Whereas the location in question has no Internet access, is there a portable computer such as a laptop or Chromebook that could be used to access the Internet at a public location such as a library or WiFi hotspot. If so, that laptop should be able to acquire a time sync. Then the portable device should be able to provide an updated time to the Hubitat. It is a cumbersome way to do it, but it should work.
If a POTS landline is available, another option might be using Internet service through a dial-up connection. There are still a few providers available. Juno has a free plan for up to 10 hours per month.
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