WiFi disconnects shortly after connection established

[Andreas Klust]

After upgrading from Ubuntu 11.10 to 12.04, wifi connected properly but the connection was dropped again after only ~5s. the problem seems to be related to IPv6. Disabling automatic IPv6 configuration in NetworkManager (see conf file option below) solves the issue for me:

/etc/NetworkManager/system-connections/Auto\ ESSID option:

[ipv6]
method=ignore

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: network-manager 0.9.4.0-0ubuntu3
ProcVersionSignature: Ubuntu 3.2.0-24.37-generic 3.2.14
Uname: Linux 3.2.0-24-generic i686
ApportVersion: 2.0.1-0ubuntu7
Architecture: i386
Date: Wed May 9 10:13:49 2012
EcryptfsInUse: Yes
IfupdownConfig:
 auto lo
 iface lo inet loopback
InstallationMedia: Ubuntu 11.04 "Natty Narwhal" - Release i386 (20110427.1)
IpRoute:
 default via 94.224.192.1 dev wlan0 proto static
 94.224.192.0/20 dev wlan0 proto kernel scope link src 94.224.204.37 metric 2
 169.254.0.0/16 dev wlan0 scope link metric 1000
NetworkManager.state:
 [main]
 NetworkingEnabled=true
 WirelessEnabled=true
 WWANEnabled=true
ProcEnviron:
 PATH=(custom, user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: network-manager
UpgradeStatus: Upgraded to precise on 2012-05-08 (0 days ago)
mtime.conffile..etc.NetworkManager.NetworkManager.conf: 2012-05-09T09:43:55.538988
nmcli-con:
 NAME UUID TYPE TIMESTAMP TIMESTAMP-REAL AUTOCONNECT READONLY DBUS-PATH
 Wired connection 1 7af65225-c8e1-4edd-a039-f799a909d7c4 802-3-ethernet 1336549897 Wed 09 May 2012 09:51:37 AM CEST yes no /org/freedesktop/NetworkManager/Settings/2
 Auto wifi51-2 b9f18346-527a-4f08-8c62-77a17b6d8de8 802-11-wireless 1336551051 Wed 09 May 2012 10:10:51 AM CEST yes no /org/freedesktop/NetworkManager/Settings/1
 Bongo 6756b39f-4887-471f-8973-8b3f023ceb7e vpn 1334517158 Sun 15 Apr 2012 09:12:38 PM CEST no no /org/freedesktop/NetworkManager/Settings/0
nmcli-dev:
 DEVICE TYPE STATE DBUS-PATH
 wlan0 802-11-wireless connected /org/freedesktop/NetworkManager/Devices/1
 eth0 802-3-ethernet unavailable /org/freedesktop/NetworkManager/Devices/0
nmcli-nm:
 RUNNING VERSION STATE NET-ENABLED WIFI-HARDWARE WIFI WWAN-HARDWARE WWAN
 running 0.9.4.0 connected enabled enabled enabled enabled disabled

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Mark Eichin (eichin-gmail)]

I just fought through literally and hour and a half of "Activation (wlan0/wireless): association took too long.", made worse by keyring problems that cause each failure to produce a prompt for the key (not the subject of this bug, that's unrelated.) Adding

[ipv6]
method=ignore

as suggested above to /etc/NetworkManager/system-connections/Auto XXXX (ssid elided as I'm a guest here) and bouncing NetworkManager to make sure it reread the file (for about the 10th time) immediately stopped the spinloop... so this probably deserves more attention. (The local wifi is WEP with a hex key, on a WRT-54G running factory firmware, which worked fine when this laptop was running Oneiric.) (local system is an x220t)

[Mathieu Trudel-Lapierre (cyphermox)]

Could these issues have been due to upgrades? If you were running into this; make sure the IPv6 connection is set to not be required to complete bringing up the interface: in other words, look at the configure in UI and uncheck "Require this..." if it's checked.

[Andreas Klust (andreas.klust-deactivatedaccount)]

Hi Mathieu,

I tried again with IPv6 on "automatic" setting and made sure that the "Require IPv6 ..." setting was unchecked. It works now fine for me.

However, I guess it works now thanks to the kernel bug fixes described in the duplicate of this bug report, bug #997774.

Thanks to everybody for the help!
Andreas