Re: Ad-hoc network: cannot ping other machine

[Patrick McMunn <doctorwhoguy gmail com>]

I was just excited to successfully create an ad-hoc network between
two Linux machines at all, even if ICS wasn't enabled. It is so easy
with Windows. Wireless networking with Linux has been a headache for
me.

But anyway, I tried creating an internet connection sharing setup, and
NetworkManager will not connect to the network I'm trying to create.
Here's the setup:

[Wireless]
SSID: share
Mode: Ad-hoc
Band: b/g
Channel: 10
BSSID: <blank>
Restrict to Interface: Any
Cloned MAC Address: <blank>
MTU: Automatic

[Wireless Security]
Security: None

[IPv4 Address]
Method: Shared
"IPv4 is required for this connection" checkbox is selected

[IPv6 Address]
Method: Disabled

/etc/NetworkManager/nm-system-settings.conf
[main]
plugins=ifnet,keyfile

[ifnet]
managed=true
auto_refresh=false

Fortunately, the created connection appears in the GUI (there is often
a problem with created connections not appearing in the GUI), and I
click on it. The status says "Configuring interface" for a few seconds
then "Setting network address for just a moment" and then goes back to
"Not connected."

To try to get some feedback, I ran dmesg. The first time shows:
[  133.491149] wlan0: Trigger new scan to find an IBSS to join
[  137.008034] wlan0: Trigger new scan to find an IBSS to join
[  141.008084] wlan0: Trigger new scan to find an IBSS to join
[  142.299155] wlan0: Creating new IBSS network, BSSID 12:e3:2c:72:57:15
[  144.242036] wlan0: no IPv6 routers present

Subsequent attempts have the same message but omit "no IPv6 routers
present" and a different BSSID.

I also ran avahi-daemon from a root console and tried to connect. Upon
starting it, I get
localhost patrick # avahi-daemon
Process 5268 died: No such process; trying to remove PID file.
(/var/run/avahi-daemon//pid)
Found user 'avahi' (UID 103) and group 'avahi' (GID 1009).
Successfully dropped root privileges.
avahi-daemon 0.6.30 starting up.
Successfully called chroot().
Successfully dropped remaining capabilities.
Loading service file /services/sftp-ssh.service.
Loading service file /services/ssh.service.
System host name is set to 'localhost'. This is not a suitable mDNS
host name, looking for alternatives.
Joining mDNS multicast group on interface wlan0.IPv6 with address
fe80::211:50ff:fef5:592f.
New relevant interface wlan0.IPv6 for mDNS.
Joining mDNS multicast group on interface eth0.IPv6 with address
fe80::211:95ff:fefd:cbd9.
New relevant interface eth0.IPv6 for mDNS.
Network interface enumeration completed.
Registering new address record for fe80::211:50ff:fef5:592f on wlan0.*.
Registering new address record for fe80::211:95ff:fefd:cbd9 on eth0.*.
Registering HINFO record with values 'I686'/'LINUX'.
Server startup complete. Host name is linux.local. Local service
cookie is 3616907344.
Service "linux" (/services/ssh.service) successfully established.
Service "linux" (/services/sftp-ssh.service) successfully established.

Then after attempting to create the ICS network avahi-daemon reports:
Joining mDNS multicast group on interface wlan0.IPv4 with address 10.42.43.1.
New relevant interface wlan0.IPv4 for mDNS.
Registering new address record for 10.42.43.1 on wlan0.IPv4.
Withdrawing address record for 10.42.43.1 on wlan0.
Leaving mDNS multicast group on interface wlan0.IPv4 with address 10.42.43.1.
Interface wlan0.IPv4 no longer relevant for mDNS.

Why is it that when I create a normal ad-hoc network, it creates an IP
address of 169.254.x.x but always tries to create an IP of 10.42.43.1
when attempting ICS? Could that be part of the problem?

Anyway, I hope this helps. If you can get ICS working for me I could kiss you.

P.S. I'm currently running kernel 3.0.6 and I'm using dhcpcd with
zeroconf support through Avahi enabled. My wireless card in the
desktop in a Belkin PCI card with a Broadcom 4318 chipset. I'm using
the kernel's b43 driver with Broadcom's wl firmware.

On 10/10/11, Dan Williams <dcbw redhat com> wrote:
> On Sat, 2011-10-08 at 23:54 -0500, Patrick McMunn wrote:
>> 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....
>
> NM uses wpa_supplicant for wifi control, so yeah, you'd need it.  WRT
> channel 10 vs. channel 3, that's very interesting; it could be that the
> driver for your wifi card is somewhat stupid; I've noticed a lot of
> variability in the quality of Ad-Hoc mode support in kernel wifi
> drivers.  For example, in certain kernel versions Ad-Hoc + WPA simply
> doesn't work.  At all.  But we'd do best to investigate deeper into the
> kernel driver here.
>
> Second, for ICS, you want to choose "Shared to other computers" as the
> IPv4 connection  method in the Ad-Hoc network you're creating.  If
> that's an option in the KDE network config (that appears to be what
> you're using...).  The method "Link-Local" will only do Link-local, it
> won't start up ICS.
>
> Dan
>
>> 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
>> >
>> > - Learn more about the Catholic Faith: http://www.catholic.com/
>> > - Pray with the Church: http://www.universalis.com/
>> _______________________________________________
>> networkmanager-list mailing list
>> networkmanager-list gnome org
>> http://mail.gnome.org/mailman/listinfo/networkmanager-list
>
>
>


-- 
Patrick McMunn

- Learn more about the Catholic Faith: http://www.catholic.com/
- Pray with the Church: http://www.universalis.com/