Re: Ad-hoc network: cannot ping other machine

[Patrick McMunn <doctorwhoguy gmail com>]

I just wanted to let anyone who runs across this know that I was able
to resolve the issue. I checked the output of dmesg on the laptop, and
I saw a message "disassociating by local choice (reason=3)" After
doing a Google search and finding this was a widely reported problem,
some of the proposed solutions included disabling power management on
the laptop's wifi card, disabling wpa_supplicant, and changing the
channel the connection is using. I was unable to disable
wpa_supplicant. If I killed the process, it respawned. If I
uninstalled wpa_supplicant completely, NetworkManager refused to work
at all. I ended up manually specifying the connection to use channel
10 as one person recommended, and voila! I was able to connect, and
each machine was able to ping the other. Now if I can just get
internet connection sharing working....

On 10/8/11, Patrick McMunn <doctorwhoguy gmail com> wrote:
> I'm using NetworkManager 0.9.1.90 (just installed yesterday; I've been
> using 0.9.0 for a while) and KNetworkManager from git. I have never
> been able to get a working ad-hoc network between two Linux machines -
> only when I create it with Windows and connect to it with a Linux
> machine.
>
> Here's my setup in KNetworkManager:
> SSID: 1337
> Mode: Ad-Hoc
> Band: b/g
> Channel: 3
> BSSID: <blank>
> Restrict to Interface: Any
> Cloned MAC Address: <blank>
> MTU: Automatic
>
> IPv4 Address: Link-Local
> IPv6 Address: disabled
>
> results of route from command line of desktop computer
>
> Kerne IP routing table
> Destination     Gateway         Genmask         Flags Metric Ref
> Use Iface
> loopback        *               255.0.0.0       U     0      0        0 lo
> link-local      *               255.255.0.0     U     2      0        0
> wlan0
> 224.0.0.0       *               240.0.0.0       U     0      0        0
> wlan0
>
> Settings are the same on desktop and laptop computers. Link-Local is
> the only setting that will work at all under IPv4 settings. DHCP
> results: attempts to connect but fails. I have dhcpcd set to fallback
> to zeroconf, but that doesn't work with NM. I haven't had any luck
> with static IPs either.
>
> When using Link-Local, however, I can connect to the network easily.
> Then I can walk over to my laptop, use KNetworkManager's scan feature
> and identify the essid I created on the desktop. I have to change IPv4
> settings to Link-Local, but everything else is usually identified
> correctly. Then I save and can connect - apparently. If I look at the
> network usage statistics of KNetworkManager, the graph indicates
> network activity for a few moments at the time I attempt to join the
> network, but then it goes back to zero never to do anything else. I
> cannot ping either machine from the other. I have tried this with no
> encryption at all for troubleshooting and with WPA Personal just to
> see what would happen - both with the exact same results (when I tried
> encryption, it even asked for my passphrase before connecting, so that
> seemed to work).
>
> Once I get this solved, I want to be able to share internet connection
> over wifi.
>
> Any ideas what's wrong?
>
> --
> Patrick McMunn
>
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