I managed to use my Raspberry Pi Zero W as hotspot. I did this headless by using SSH and my Ubuntu 17.10 laptop.
All I installed was
nginx which serves as a web server as well as
dnsmasq to use it as a hotspot.
After rebooting the system I can no longer access the Raspberry Pi via SSH. I see that the hotspot works since my laptop detects a new wi-fi network but it does not recognize the Raspberry Pi via USB anymore. Ubuntu says "Cable unplugged" when opening the Network.
I tried a lot of tutorial the last hours but I have still not managed to access it via SSH.
How could I possibly access my Pi via SSH again? What for information would you need? I really do not want to repeat the whole process from copying the image file to the SD card to setting up all the programs I need.
I would be really glad if someone would help me to solve this problem!