How to run at boot? How to run automatically?

[bjohas]

Hello,

thanks for the script - this is just what we are looking for!

We're in an Option 2 / Option 6 scenario, and I've used Option 6 to switch back and forth. However, we'd like to do this at boot.

Here's our scenario:

• We have a RPi Zero W.
• On boot, the RPi should look for networks. (I guess this is just the normal process.)
• If a known network is available, it should connect. (Again, nothing unusual here.)
• If no known network is available, it should create a hotspot. (In other words, if some time after boot, no internet connection has been made, then hotspot mode should be enabled.)
• We'd then want to access a web server running on 10.0.0.5 to add new network details. (That's easily done.)
• The RPi should try to connect to the new network, or otherwise return to hotspot mode.

My question is this: Is it correct that the script must be run interactively?

The description says: "AutoHotspot Setups: This script is for installing a Raspberry Pi WiFi setup where the Pi will connect to a previously configured Wifi network when the Pi is in range of the router or Automatically setup a Raspberry Pi access point when a known wifi network is not in range. "

Having explore the manual options, how do we automate this?

Many thanks!

[RaspberryConnect]

Hi

You are welcome, im glad you find it useful.

The autohotspot script does what you need by design. The github script is just an installer and for setup, Option 6 is for testing.
By default the installed autohotspot script will check the wifi status at boot. If no known wifi network is found then it will generate a hotspot which will stay in place until a reboot.
But if you re-run the script manually
sudo /usr/bin/autohotspot (this is option 2, if you use option 1 then it will be sudo /usr/bin/autohotspotN)
the wifi will be re-assessed and if the wifi status has changed then the script will make the switch, either way without the need to reboot.
you can also re-run the service for the same effect
sudo systemctl start autohotspot.service

It is also possible to add a cron task and run the script every 5 mins for example, then the switch will happen as an when the wifi network goes in and out of range. Though if your wifi network signal is weak the pi could switch unexpectedly, causing the connection to Pi via the hotspot to be lost or it could disappear from the wifi network. But may be of use.
The manual guide on my website has info on the cron timer near the bottom of the article called Setting up a timer:
https://www.raspberryconnect.com/projects/65-raspberrypi-hotspot-accesspoints/158-raspberry-pi-auto-wifi-hotspot-switch-direct-connection

Good luck with your project

[bjohas]

Thank you - that's really helpful.

Can I check a few things?

Question 1. The scripts will only run at boot time, correct? So the only purpose of the service is to run the script at boot time, rather than monitoring and running the script from time to time? (To me, the answer to this is yes. If I want to run the script regularly, I would use the timer, as described.)

Question 2. Suppose I wanted the script, but without running it at boot time? In other words, only run the script as needed. Would the correct process be to install the script (e.g. Options 1 or 2, as required), and then disable the service?(Again, I'm assuming the answer is yes.)

Question 3. For our use-case, we also want to be able to turn wifi off (to save power). We'll test this, but just in case it's obvious to you. Would you expect sudo ifdown wlan0 / sudo ifup wlan0 to work also in the hotspot mode?

Many thanks!

[RaspberryConnect]

Hi

1: Yes the service is just for automatic start at boot time.
Unfortunately a systemd timer doesn't work with the script so it can't be repeated with that so another script or Cron is the best way to rerun the script at intervals.

2: yes, install and disable the service. Though wpa_supplicant will be disabled in /etc/dhcpcd.conf so you will get no wifi network connection. To reactivate it comment out the line nohook wpa_supplicant
If you re-enable the service then that needs to un-commented.
That will stop it at boot. Then manually run sudo /usr/bin/autohotspot (option2) or you can run the service sudo systemctl start autohotspot as this will also run the autohotspot script once on demand.

3: ifup and ifdown use the /network/interfaces file i believe which is depreciated on the PiOS so you will need to use
ip link set dev wlan0 down and ip link set dev wlan0 up
However if you bring wlan0 down while the access point is running, you will need to bring wlan0 up and then run the autohotspot straight after as hostapd will not restart on it's own.
You can bring wlan0 down and up while connected to a wifi network ok with ip link set dev wlan0 down / up
if it does not come back up properly then rebind dhcpcd with sudo dhcpcd -n wlan0
which will do the trick.