I use one of my Raspberry Pi as a headless desk clock and, apart from a reboot once a day which forces the OS to synchronise time to an NTP server, I would like to turn the WiFi off after that stage has completed, perhaps with a 10 minutes grace period in case I need to SSH in to perform maintenance.
Is there an easy way to do this?
timeout 10m ifconfig wlan0 down
ExecStart=timeout 10m ifconfig wlan0 down
" that mean when the RPi start , the Rpi start your service and others services (ex:networking,you have internet) and then execute the ifconfig command after 10m (timeout). When the interface is put in down the connectivity is stopped (you have not internet).