Our modem failed recently and we were without internet access for a day until it was replaced. Our SmartThings hub (V2) was also knocked offline when this happened. The problem we encountered was for that night we were without our SHM alarm system. Our young son started a recent sleepwalking habit, so I ended up having to sleep on a (uncomfortable) mat by the top of the stairs to catch him from possibly leaving the house at night.
If this happens in the future, what are my options for enabling the alarm without internet/app access?
Unfortunately, SmartThings is Primarily a cloud-based system, as you’ve discovered. While there are a few bits of SHM (classic app) or SHTM (New V3 app) which can work without the cloud, it’s not enough to make a satisfactory security system for most people. For example, there is no way to change the security. mode from arm to disarm or back again. You can’t use the app at all to control devices, even if your phone is on the same Wi-Fi. You can’t change location mode from home to away or back again. You can’t receive any notifications. You could have a set up so that triggering a sensor would set off a siren, which might be good for an outbuilding, but because of all the other limitations it’s not usually something you want to do inside your own house.
https://support.smartthings.com/hc/en-us/articles/209979766-Local-processing
Honestly, the best thing to do is just to buy a different inexpensive purpose built security system to cover your security needs. Something which does run locally without needing the Internet.
3 Likes
Agree 100%. I ran iSmartAlarm when I was on ST. They didn’t interact with each other but I knew i could always change my iSmartAlarm setting with the keyfob.
2 Likes
Thanks for the suggestions. Honestly I guess I didn’t think it through all the way and took having internet access 24/7 for granted. I falsely assumed local wifi would stay up without internet access because of my separate UniFi access points. It did not, and from your info it wouldn’t have mattered regarding access to the ST app anyway.
Is there any separate alarm solution with ST integration? I’ve loved being able to turn the lights on when the alarm is triggered.
Nothing seamless or official at this point.
Anything with an Ifttt channel may give you enough to integration to turn the lights on as long as the Internet is available.
And many security systems have their own integration with lights, so there’s that as well. 
A Phillips hue bridge is the one most likely to be able to work with both smartthings and another system at the same time, and you can have one bulb turning on be the trigger for lots of other events. That may even be able to work when the Internet is down, it just depends on the exact set up.
Beyond that, there are lots of partial integrations that various people have set up using various methods with various systems. You just have to look into each one to see if it matches what you want to do.
To find these, look on the quick browse lists in the community – created wiki, look down near the bottom of that page for the “project reports“ section, then look for the list on “security.“
1 Like
Another option that could work for some people is a UPS and a router that allows failover to 3G/4G mobile data. Requires a sim card with a data plan, but there are pay as you go plans without monthly fees. For a while you could get a Freedom Pop sim card with a free nominal amount of data.
2 Likes
Absolutely agree. I’ve had a stand-alone security system for over 10 years that’s cellular-based and extremely reliable. For many reasons, SmartThings is a very nice Home Automation system that’s just not a reliable security system.
2 Likes