I am having problems with my wireless adapter on Ubuntu 14.04. Sometimes when I boot the computer it is able to establish a connection, maybe one fifth of the time, but mostly it is just trying to connect forever:
% nmcli nm
RUNNING STATE WIFI-HARDWARE WIFI WWAN-HARDWARE WWAN
running connecting enabled enabled enabled disabled
Even when it is able to establish a connection there are problems. After a long uptime the connection seems to get congested and is often dropped. The same thing happens if I try to stream video or download large files.
My current hardware setup is somewhat peculiar. I spilled soda all over my other laptop, ruining the motherboard, so I decided to put this hard drive into my old one (the one I am currently on) in order to keep all my files and settings. Everything worked right away except for the wifi.
On that old machine I had noticed problems with the wireless connection under low signal strength. I solved that problem by downgrading and putting the bcmwl-kernel-source on hold using apt-mark. But that option doesn't seem to exist for my current drivers. I have since purged the obsolete drivers to make sure there is no conflict, but that had no effect on the problem.
Other threads prompted my to try the following, but to no avail:
sudo apt-get install --reinstall linux-firmware
sudo modprobe -r iwlwifi
sudo modprobe iwlwifi
System info:
% sudo lshw -C network
*-network
description: Wireless interface
product: Centrino Wireless-N 2230
vendor: Intel Corporation
physical id: 0
bus info: pci@0000:02:00.0
logical name: wlan0
version: c4
serial: 60:6c:66:32:96:f5
width: 64 bits
clock: 33MHz
capabilities: pm msi pciexpress bus_master cap_list ethernet physical wireless
configuration: broadcast=yes driver=iwlwifi driverversion=4.2.0-35-generic firmware=18.168.6.1 latency=0 link=no multicast=yes wireless=IEEE 802.11bgn
resources: irq:33 memory:f7d00000-f7d01fff
% rfkill list
1: phy0: Wireless LAN
Soft blocked: no
Hard blocked: no
2: asus-wlan: Wireless LAN
Soft blocked: no
Hard blocked: no
3: asus-bluetooth: Bluetooth
Soft blocked: yes
Hard blocked: no
% dmesg | grep iwl
[ 9.487676] iwlwifi 0000:02:00.0: can't disable ASPM; OS doesn't have ASPM control
[ 9.514737] iwlwifi 0000:02:00.0: loaded firmware version 18.168.6.1 op_mode iwldvm
[ 9.566860] iwlwifi 0000:02:00.0: CONFIG_IWLWIFI_DEBUG disabled
[ 9.566863] iwlwifi 0000:02:00.0: CONFIG_IWLWIFI_DEBUGFS enabled
[ 9.566865] iwlwifi 0000:02:00.0: CONFIG_IWLWIFI_DEVICE_TRACING enabled
[ 9.566868] iwlwifi 0000:02:00.0: Detected Intel(R) Centrino(R) Wireless-N 2230 BGN, REV=0xC8
[ 9.566968] iwlwifi 0000:02:00.0: L1 Enabled - LTR Disabled
[ 9.630114] ieee80211 phy0: Selected rate control algorithm 'iwl-agn-rs'
[ 10.361252] iwlwifi 0000:02:00.0: L1 Enabled - LTR Disabled
[ 10.368831] iwlwifi 0000:02:00.0: Radio type=0x2-0x0-0x0
[ 10.613667] iwlwifi 0000:02:00.0: L1 Enabled - LTR Disabled
[ 10.621565] iwlwifi 0000:02:00.0: Radio type=0x2-0x0-0x0
% sudo iwlist wlan0 scan
wlan0 Scan completed :
Cell 01 - Address: A0:21:B7:AC:C1:3C
Channel:11
Frequency:2.462 GHz (Channel 11)
Quality=39/70 Signal level=-71 dBm
Encryption key:on
ESSID:"JsNet"
Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 11 Mb/s; 6 Mb/s
9 Mb/s; 12 Mb/s; 18 Mb/s
Bit Rates:24 Mb/s; 36 Mb/s; 48 Mb/s; 54 Mb/s
Mode:Master
Extra:tsf=000000001928e67b
Extra: Last beacon: 32ms ago
IE: Unknown: 00054A734E6574
IE: Unknown: 010882848B960C121824
IE: Unknown: 03010B
IE: IEEE 802.11i/WPA2 Version 1
Group Cipher : CCMP
Pairwise Ciphers (1) : CCMP
Authentication Suites (1) : PSK
IE: Unknown: 2A0100
IE: Unknown: 32043048606C
IE: Unknown: DD180050F2020101830003A4000027A4000042435E0062322F00
IE: Unknown: DD1E00904C33CC111BFFFF000000000000000000000000000000000000000000
IE: Unknown: 2D1ACC111BFFFF000000000000000000000000000000000000000000
IE: Unknown: DD1A00904C340B001B00000000000000000000000000000000000000
IE: Unknown: 3D160B001B00000000000000000000000000000000000000
IE: Unknown: DD0900037F01010000FF7F
IE: Unknown: DD0A00037F04010002004000
IE: Unknown: DD860050F204104A0001101044000102103B0001031047001000000000000010000000A021B7ACC13C1021000D4E6574676561722C20496E632E10230008574E4452333730301024000456314831104200046E6F6E651054000800060050F204000110110017574E445233373030763228576972656C65737320415029100800020086103C000103
% sudo iw wlan0 scan
BSS a0:21:b7:ac:c1:3c (on wlan0)
TSF: 742840547 usec (0d, 00:12:22)
freq: 2462
beacon interval: 100
capability: ESS Privacy ShortPreamble ShortSlotTime (0x0431)
signal: -71.00 dBm
last seen: 0 ms ago
SSID: JsNet
Supported rates: 1.0* 2.0* 5.5* 11.0* 6.0 9.0 12.0 18.0
DS Parameter set: channel 11
RSN: * Version: 1
* Group cipher: CCMP
* Pairwise ciphers: CCMP
* Authentication suites: PSK
* Capabilities: (0x0000)
ERP: <no flags>
Extended supported rates: 24.0 36.0 48.0 54.0
WMM: * Parameter version 1
* u-APSD
* BE: CW 15-1023, AIFSN 3
* BK: CW 15-1023, AIFSN 7
* VI: CW 7-15, AIFSN 2, TXOP 3008 usec
* VO: CW 3-7, AIFSN 2, TXOP 1504 usec
HT capabilities:
Capabilities: 0x11cc
HT20
SM Power Save disabled
RX HT40 SGI
TX STBC
RX STBC 1-stream
Max AMSDU length: 3839 bytes
DSSS/CCK HT40
Maximum RX AMPDU length 65535 bytes (exponent: 0x003)
Minimum RX AMPDU time spacing: 8 usec (0x06)
HT RX MCS rate indexes supported: 0-15
HT TX MCS rate indexes are undefined
HT operation:
* primary channel: 11
* secondary channel offset: no secondary
* STA channel width: 20 MHz
* RIFS: 0
* HT protection: non-HT mixed
* non-GF present: 0
* OBSS non-GF present: 1
* dual beacon: 0
* dual CTS protection: 0
* STBC beacon: 0
* L-SIG TXOP Prot: 0
* PCO active: 0
* PCO phase: 0
WPS: * Version: 1.0
* Wi-Fi Protected Setup State: 2 (Configured)
* Response Type: 3 (AP)
* UUID: 00000000-0000-1000-0000-a021b7acc13c
* Manufacturer: Netgear, Inc.
* Model: WNDR3700
* Model Number: V1H1
* Serial Number: none
* Primary Device Type: 6-0050f204-1
* Device name: WNDR3700v2(Wireless AP)
* Config methods: Ethernet, Label, PBC
* RF Bands: 0x3
