[pkg-wpa-devel] A challenge: wpa_supplicant + wlan button + zeroconf

[Kel Modderman]

Felix Homann wrote:
> Hi again,
>
> here's a challenge:
>
> Show me how this will work with the new approach:
>
> 1. I've got one wpa-psk network configured in my wpa_supplicant.conf (the 
> default/home network)
> 2. I've got a second entry to connect to any open access point.
> 3. I want to get an IP by DHCP by default.
> 4. I want to have zeroconf as a fallback (if DHCP fails).
> 5. I want to be able to switch the network on/off with my notebook's wlan 
> button even without logging in and manually ifupping the interface first.
> 6. I don't want to wait on boot for a minute or so if there is no AP or the 
> radio is switched off.
>
> This has been working before (and is again) with the "mode 3"-daemon together 
> with ifplugd.
>
> As I've written in another thread I have solved the main issues, but I have to 
> disable the zeroconf fallback. While I first thought this was not that 
> important it is actually a step back.
>
> Here's the preliminary solution:
>
> /etc/network/interfaces:
> ==============
>
> auto lo wlan
> iface lo inet loopback
> iface wlan inet manual
>        wpa-conf /etc/wpa_supplicant/wpa_supplicant.conf
>        wpa-action-timeout -1
>        # the example wpacli-action-dhclient script:
>        wpa-action /etc/wpa_supplicant/roaming.sh 
>        wireless-powerperiod 4
>
> /etc/default/zeroconf:
> =============
>
> #IFBLACKLIST="wlan"
> FALLBACK=yes
>
> -----------------------
>
> Here are the problems:
>
> 1.  With this setup zeroconf will run on the interface. I won't get an IP via 
> DHCP. I have to increase wpa-action-timeout to prevent this.
> 2. If I increase wpa-action-timeout boot will hang for the given time if the 
> radio is switched off or there is no configured AP.
> 3. If I don't set wlan to auto I have to manually ifup the interface, i.e. I 
> have to login.
>
> My temporary non-solution is to uncomment the IFBLACKLIST line 
> in /etc/default/zeroconf. My only solution so far is to get back to the init 
> script + ifplugd.
>
> So, those of you who dislike the init script, show me how this will work in 
> the new order.
>   


Could you please briefly explain what zeroconf is, why it is required, 
and what does it do? (I've never heard of it before).

Thanks, Kel.