Raspberry Pi Auto-Hotspot

Initial software from http://blog.sip2serve.com/post/48420162196/howto-setup-rtl8188cus-on-rpi-as-an-access-point

The concept of headless Pi at Jams and in classrooms has always been a subject close to my heart and recently I’ve been trying to go down the route of a Pi that see if it gets an IP address from a DHCP server, if not – it turns itself into a hotspot so that other computers can connect and communicate to it over WiFi.

So sequence should be

1.  Check if IP been handed out on WiFi from a DHCP server – if OK End

2.  If not, create hotspot for other Pi/clients to use.

The basic software needed is something called hostapd to make the Pi appear as a WiFi access point and dnsmasq so that it can hand out ip addresses to anything connecting to it.

Current situation

Note:  Hopefully this current state will be taken over by @heeedt  https://github.com/heeed/hotpi

Working Hotspot (but no automatic changeover) using 8188CUS based adaptors

To get this working you need to connect your Pi to the internet using a LAN cable.

Then copy and paste this into an LX Terminal session

wget http://git.io/wZV8tg -O ipispot.sh

and then type

sudo bash ipispot.sh

You will be asked a series of questions but unless you an advanced geek or the network you are running on is using 10.0.0.xx addresses – just accept the default for each question

The only exceptions to this would be for your country and WiFi channel number

At the end, it will ask to reboot – once done, you should now see a open ClassPi available WiFi connection that you can connect to.

The hotspot does not supply a bridged connection to your LAN and the internet – (it would be an access point if it did that) it is purely designed to let you connect to it from a WiFi laptop or any WiFI enabled device such as as tablet

Please try and give me feedback


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11 Responses

  1. weehorsey says:

    Hi cymplecy

    Works great, been wanting to do this for a while.
    However how do I easily revert back to non hotspot mode?



    • cymplecy says:

      The idea is to make it auto-matic so that if it finds a known wifi (e.g at home) then it conencts to that and only goes into hotspot mode when it can’t find normal situation (e.g at a Jam or a mates house)

      So stage 2 is to do that bit 🙂


  2. Mark Pearson says:

    Simon – thanks for this – it is looking very good so far.

    One thing I noticed, the script gathers security info, but the generated hostapd.conf file has the security parameters commented out – so the access point comes up with no security in place. Might be worth letting people know about this – and which file to mod if they want to enable security.

    I’m almost up and running – works fine with no security, but when I uncomment the lines in hostapd.conf I can see the AP network, and connect but it gets stuck in an Authentication loop (possibly getting IP ) – but then I had a similar problem when I was setting up an Access point manually (Adafruit tutorial) – must be something I’m doing wrong – or maybe my network dongle – I’ll keep going and see what I can discover.

    • cymplecy says:

      I’m a no security person 🙂 (there’s always a way to crack WiFi so I never botherin the first place)

      The idea is that this will be a fallback mode when it can’t find its normal AP and for primary classrooom use so no password is a requirement but I’ll try and see which lines need uncommenting to enable the password 🙂


      • Mark Pearson says:

        Well I’m certainly not a security expert either 🙂 But having just wrestled with this topic and reading multiple online tutorials last week, the topic is fairly fresh for me.

        I believe that after running your script, if you uncomment the lines in the file /etc/hostapd/hostapd.conf and reboot it should come up in “secure” mode and need a WPA/2 password etc.

        Using your script and a different wifi dongle (Edimax) I have a nice “secure” access point working fine – so I suspect that my cheapo £2 wifi dongle is the main problem I was experiencing – it works in AP (access point) mode as long as I don’t require WPA/2 security.

        Thanks for the really useful script – the whole topic continues to be a learning experience for me 🙂

  3. Worth noting that wifi dongles are limited to the number of connections they can make in AP mode,
    and some have really low limits:
    e.g. TP-LINK TL-WN722N can only handle SEVEN clients
    Simon is using the RTL8188CUS which can go up to 32

  4. Hi Simon

    you say in your Readme that you have this working on a Ralink RT5370 adapter but the current file checks for an RTL8188CUS and throws up an error message if not present. What changes do I need to make to get it to work with the 5370 please.

    Cheers, Daz.

  5. steve gale says:


    I have tried to do this following other instructions and failed, so having seen your post and the successful comments above thought I would give it a try.
    I have copied the line wget …. into a terminal as suggested, press enter and get the following error,
    HTTP request sent, awaiting response… 302 Found
    Location: https://raw.githubusercontent.com/cymplecy/pispot/master/install_hotspot8188CUS.sh [following]
    –2014-09-30 13:34:46– https://raw.githubusercontent.com/cymplecy/pispot/master/install_hotspot8188CUS.sh
    Resolving raw.githubusercontent.com (raw.githubusercontent.com)…
    Connecting to raw.githubusercontent.com (raw.githubusercontent.com)||:443… connected.
    GnuTLS: A TLS packet with unexpected length was received.
    Unable to establish SSL connection.
    any ideas what the problem could be?

    I am using a Dexter Industries image but with the text with the above error do not believe this is the problem. Later on this week I will try it with my wheezey image

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