Ad-hoc network: cannot ping other machine

[Patrick McMunn <doctorwhoguy gmail com>]

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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