Every Raspberry Pi Zero W I’ve had has had intermittent connection problems on Wi-Fi. I’ve been able to fix the problems by disabling power management on the Wi-Fi interface each time. This page gave me my preferred solution for taking care of the problem on each machine. I’m duplicating the information here to contribute/prevent webrot.
See the current state of power management:
sudo iw wlan0 get power_save
set power management off:
sudo iw wlan0 set power_save off
Create a systemd unit file to set Wi-Fi power management:
sudo systemctl --full --force edit wifi_powersave@.service
With this as the contents of the unit file:
[Unit] Description=Set WiFi power save %i After=sys-subsystem-net-devices-wlan0.device [Service] Type=oneshot RemainAfterExit=yes ExecStart=/sbin/iw dev wlan0 set power_save %i [Install] WantedBy=sys-subsystem-net-devices-wlan0.device
Then enable the unit file, setting power management to off whenever wlan0 is activated.
sudo systemctl disable email@example.com
sudo systemctl enable firstname.lastname@example.org