If you start over and rewrite the image to the SD card, the first boot will again work ok, it's only rebooting that breaks Wifi. Running setup-alpine again at this point also doesn't work.

I decided to not install the rngd related packages at this point to see how a reboot looked, answer is not good. Setup script completes and I was able to connect to WiFi and pull down packages etc. First boot after writing the image to the SD card seems to work ok as far as WiFi functionality is concerned. Update - I went through installation again on a Pi Zero W with Alpine 3.10.3 for armhf. I'm still learning about Alpine Linux and hope to improve this process as I do more reading and experimentation. Some steps may not be necessary for your use case and some steps may not be necessary at all, but don't seem to hurt. I need to go back through this again but it should work as written. When the networking service was set to 'boot' (which it was out of the box) it was starting before rngd and wpa_supplicant so wlan0 would never connect. It also adds the rngd and wpa_supplicant services to start at boot and removes the network service from the rc-update list completely, which seems like the wrong thing to do and probably is - networking still gets started, probably as a dependency to something else, and it starts after rngd and wpa_supplicant, which is what I needed.

The solution documented below adds and starts the rngd service prior to running setup-alpine which fixes the wifi connection problems and allows you to walk through the setup script successfully. I had problems with it initially as WiFi wouldn't connect when going through the setup-alpine script and when I was able to get it connect (after numerous failed manual attempts) it wouldn't reconnect on reboot. This wiki describes how I installed Alpine Linux 3.9.2 armhf on a Raspberry Pi Zero W.

Make sure no other pages link here and check the page's history before deleting.

This page may be consolidated into the main Raspberry Pi installation page and then deleted. Open a plaintext editor such as Notepad (Windows) or TextEdit (Mac) and create a new file.This material is proposed for deletion.

Raspberry pi zero w wireless setup