Topics

RPi / DRAWs Connectivity in the Field and at Home #draws #field #networking #avahi

john.chabalko@...
 

This is probably more of a RaspberryPI question than it is a DRAWs specific question but i think this is likely a pretty common use case amongst DRAWs users.

I use my RPi/DRAWs at home and outside (remote). At home i have it join my home wifi on boot, i have a static IP address assigned to it at startup via DHCP and a DNS name assigned to that static IP. I connect to it via VNC or ssh/terminal. It works great.

What the configuration to do you use when you're out in the field and want a reliable connection to it via VNC/ssh? I'm assuming setting it up as an access point and connecting to that access point with your tablet laptop, and then to the RPi via VNC? Similar to this (either bridged, or just a standalone access point)?

Does anyone have guidance on the "ideal" or most reliable way to do this for radio use?

Jim Erickson
 

I do the opposite actually. My raspberry pi’s connect to my home network via Ethernet, which I statically map with dhcp and then I set the WiFi on the pi up to be an access point using dnsmasq and hostapd.  Then when I’m in the field, I connect to my pi’s WiFi and use VNC or ssh or whatever. 

I’m just in the middle of configuring a pi with the new Draws_10 image and I do have some notes I could share if interested. 

Jim

On Apr 2, 2019, at 16:40, john.chabalko@... wrote:

This is probably more of a RaspberryPI question than it is a DRAWs specific question but i think this is likely a pretty common use case amongst DRAWs users.

I use my RPi/DRAWs at home and outside (remote). At home i have it join my home wifi on boot, i have a static IP address assigned to it at startup via DHCP and a DNS name assigned to that static IP. I connect to it via VNC or ssh/terminal. It works great.

What the configuration to do you use when you're out in the field and want a reliable connection to it via VNC/ssh? I'm assuming setting it up as an access point and connecting to that access point with your tablet laptop, and then to the RPi via VNC? Similar to this (either bridged, or just a standalone access point)?

Does anyone have guidance on the "ideal" or most reliable way to do this for radio use?

 

What the configuration to do you use when you're out in the field and want a reliable connection to it via VNC/ssh?
That would be a use case for a 44 net VPN.

john.chabalko@...
 

I also haven't figured out yet (due to lack of time on the clock) what the best state for the RPi to be in with regard to internet connectivity. Much of my operating will be done somewhere there's a cell signal, and i can use my phone/tablet as an access point - which would get connectivity to the Pi.

I haven't yet but was going to look into how to get location data from the phone rather than the GPS.

Or should i scratch all that and treat the Pi as a disconnected device except when i'm at home?

I could run a piece of ethernet to it but i've been trying to decrease the amount of wiring i've got running around my radio. The way you suggest though Jim would work for what i'm trying to do. I think i can also have the Pi connect to my home wifi and offer up a different SID for me to connect to it - like you do. I'll look into that as well.

I'll also check out 44 net VPN - thanks for that suggestion Bill

 

Raspbian runs Avahi services, which means the computer can be discovered automatically using the Zeroconf system (Bonjour, Avahi, etc.)

If your raspberry pi is named DRAWS-CALLSIGN, then you should be able to access it from other machines like this

ssh draws-callsign.local
or
http://draws-callsign.local:8080

as long as the computers are on the same LAN.  Bonjour is built into most Apple products, Avahi/Zeroconf in many Linux/Android systems. If your Windows box doesn't have it, install iTunes.





John D. Hays
Edmonds, WA
K7VE

   


 


On Tue, Apr 2, 2019 at 5:52 PM <john.chabalko@...> wrote:


I'll also check out 44 net VPN - thanks for that suggestion Bill
_

Getting GPS from your phone/tablet will be difficult unless they are running gpsd or similar.  You can USB tether or use your phone as a WiFi Hotspot.  Another option is a 4G LTE USB dongle and SIM card for the field -- or a router like in the video discussing 44-net VPN


--


John D. Hays
Edmonds, WA
K7VE

   

Julian OH8STN <julian@...>
 

Its very simple to use your raspberry pi to connect to your home network when you're at home, or to act as an access point in the field. 
Here's the tutorials used. Read all the comments before you begin the tutorial. https://thepi.io/how-to-use-your-raspberry-pi-as-a-wireless-access-point/#comment-6316

This picture was from my outing today. I was operating the Raspberry Pi as an access point. I connected to my Raspberry Pi with my Android tablet over VNC. 

Hope this helps
73
Julian 


Julian OH8STN
www.oh8stn.org
www.youtube.com/c/OH8STN

On 3 Apr 2019 04:01, John D Hays - K7VE <john@...> wrote:

On Tue, Apr 2, 2019 at 5:52 PM <john.chabalko@...> wrote:


I'll also check out 44 net VPN - thanks for that suggestion Bill
_

Getting GPS from your phone/tablet will be difficult unless they are running gpsd or similar.  You can USB tether or use your phone as a WiFi Hotspot.  Another option is a 4G LTE USB dongle and SIM card for the field -- or a router like in the video discussing 44-net VPN


--


John D. Hays
Edmonds, WA
K7VE

   


john.chabalko@...
 

Thanks Julian, I actually went and watched your video on this last night (again) too. 

I’ll check that link tonight. I’m going to try to take it out away from the house this weekend and make sure I’ve got a workable setup

Douglas
 

Could someone email me and see what i'm doing wrong?  I can't seem to get the hotspot to work on my pi, with or without the draws hat.  I used the instructions that julian linked to.

--
Granada Estates Neighborhood Watch

Jay L.
 

Try this one from KM4ACK.  https://youtu.be/QZtAOLcY5dY


On Wed, Apr 3, 2019, 20:51 Douglas KI7LIK <KI7LIK.AZ@...> wrote:
Could someone email me and see what i'm doing wrong?  I can't seem to get the hotspot to work on my pi, with or without the draws hat.  I used the instructions that julian linked to.

--
Granada Estates Neighborhood Watch

john.chabalko@...
 

I'd be happy to help you troubleshoot Douglas. For this sort of thing whether you have the DRAWs hat or not won't matter, this is simply a rpi/linux networking configuration.

Do you have access to your rpi on a monitor and are you able to troubleshoot the networking configuration?

John Roy
 

The instructions Julian provided were excellent. Easy to follow and worked the first time. But if I read correctly, the original poster is needing a way to connect wirelessly to the home network, and then when in the field, have the Pi realize that there is no home network and start the wireless hotspot. That is exactly what I need also. I really don't want yet another box (network extender), power cable, and LAN cable taking up space.  That is the whole reason I wanted the DRAWS in the first place, to eliminate clutter. Why did I go ahead and try Julian's recommendation? Because even though it wasn't what I needed, I needed to make sure that I was actually capable of following instructions! I have tried 3 different tutorials and none of them have worked.  After 3 failed attempts, I was truly beginning to think it was operator error. 

 

You can put more than one network stanza in wpa_supplicant.conf 



On Thu, Apr 4, 2019, 19:18 John Roy <johnroy71@...> wrote:
The instructions Julian provided were excellent. Easy to follow and worked the first time. But if I read correctly, the original poster is needing a way to connect wirelessly to the home network, and then when in the field, have the Pi realize that there is no home network and start the wireless hotspot. That is exactly what I need also. I really don't want yet another box (network extender), power cable, and LAN cable taking up space.  That is the whole reason I wanted the DRAWS in the first place, to eliminate clutter. Why did I go ahead and try Julian's recommendation? Because even though it wasn't what I needed, I needed to make sure that I was actually capable of following instructions! I have tried 3 different tutorials and none of them have worked.  After 3 failed attempts, I was truly beginning to think it was operator error. 

john.chabalko@...
 

I've got this working, it does exactly what i was looking for. It will join my home Wifi when i'm at home, and if my home wifi is unavailable (eg: i'm out somewhere) it'll configure a static IP address on the RPi wlan0 interface, fire up a hotspot and i can connect to that from my computer/tablet/phone and use the Rpi as a standalone device.

Here's the link i ended up following.

It's a little bit fiddly in that it seems to take a while to bring up the access point after reboot. I was debugging the autohotspot script and all i can see is that it fails while provisioning the interface due to device busy, but then after ~2 minutes it works (i run the pi headless so am looking at the logs after the fact.

SSid's in range:  ++ iw dev wlan0 scan ap-force ++ egrep '^BSS|SSID:' command failed: Device or resource busy (-16)

The next thing i'm going to mess around with is if i can get it to join the "personal hotspot" from my phone/tablet and let me connect to it and have internet access from the RPi while i'm not at home.