My findings: right after boot there is no wireless connection. But after "rmmod iwlagn; modprobe iwlagn", all is fine. So even without adding "options iwlagn 11n_disable=1" to /etc/modprobe.d/.
System information: Xubuntu 11.10 Linux safecracker 3.0.0-14-generic #23-Ubuntu SMP Mon Nov 21 20:34:47 UTC 2011 i686 i686 i386 GNU/Linux 03:00.0 Network controller: Intel Corporation PRO/Wireless 5100 AGN [Shiloh] Network Connection -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to network-manager in Ubuntu. https://bugs.launchpad.net/bugs/836250 Title: [Oneiric] [Regression] Intel Corporation Centrino Ultimate-N 6300 poor networking, packet loss and very slow Lenovo X201 and T500 laptops Status in The Linux Kernel: In Progress Status in “linux” package in Ubuntu: Triaged Status in “network-manager” package in Ubuntu: Confirmed Status in “linux” source package in Oneiric: Triaged Status in “network-manager” source package in Oneiric: Confirmed Status in “linux” source package in Precise: Triaged Status in “network-manager” source package in Precise: Confirmed Bug description: This may be either network-manager or kernel, depending on triage... I have verified this on both a Lenovo X201 and a Lenovo T500 laptop. Both work perfectly with fully updated 10.10 and 11.04 versions of Ubuntu. However, booting into a fully updated 11.10 (as of 28/08/11) I get very poor wireless networking performance. Between 6-10% packet loss, very very slow connection and transfer rate. All in all, practically unusable. I have reported the bug on the X201 laptop, I will add the similar logs from the T500 also if required. As soon as I swap back to either 10.10 or 11.04 I get perfect wireless, it's only on 11.10 that I get problems, this would suggest it's not hardware or configuration on my side. I have had this since first installing 11.10 which was a little after Alpha 2. Wired connection is fine. ProblemType: Bug DistroRelease: Ubuntu 11.10 Package: network-manager 0.9.0-0ubuntu1 ProcVersionSignature: Ubuntu 3.0.0-9.14-generic 3.0.3 Uname: Linux 3.0.0-9-generic x86_64 Architecture: amd64 CRDA: Error: [Errno 2] No such file or directory Date: Sun Aug 28 21:26:05 2011 EcryptfsInUse: Yes Gconf: IfupdownConfig: auto lo iface lo inet loopback InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Alpha amd64 (20110803.1) IpRoute: default via 192.168.100.1 dev eth0 proto static 192.168.100.0/24 dev eth0 proto kernel scope link src 192.168.100.41 Keyfiles: Error: [Errno 2] No such file or directory NetworkManager.state: [main] NetworkingEnabled=true WirelessEnabled=true WWANEnabled=true WimaxEnabled=true ProcEnviron: LANGUAGE=en_GB:en PATH=(custom, user) LANG=en_GB.UTF-8 SHELL=/bin/bash SourcePackage: network-manager UpgradeStatus: No upgrade log present (probably fresh install) To manage notifications about this bug go to: https://bugs.launchpad.net/linux/+bug/836250/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp
