These Websites like Blynk or Cayenne but as I think i know, they connect to their Servers and when they are down my doors wont open. also i want it local in my Network with an open port to which I can connect from the Internet.
I love Blynk and use it for all my home automation projects. You can install a local Blynk server on your own network is you prefer, but I’ve been using their cloud servers for a couple of years and reliability and up-time is excellent. You can check the current server status and up time here:
https://www.blynk.cc/status
There’s nothing to stop you setting-up a small test project using a free Blynk Cloud based account and trying it for yourself. If you then decide to migrate to using your own local Blynk server you can. With the local server you can give yourself as much free ‘energy’ as you want, so app widgets don’t cost you anything.
There are plenty of examples of garage door openers built with Blynk on their community website:
https://community.blynk.cc/search?q=garage%20door%20%23projects
Pete.