Top 15.04 frequently asked interview questions
My wifi connection has gone unstable and I suspect it has something to do with upgrading to 15.04.
I am working on a Lenovo Yoga 2 (not pro) laptop. The wireless card is Intel 7260, the driver is iwlwifi.
In case that is useful, here is additional info:
>> cat /etc/lsb-release
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=15.04
DISTRIB_CODENAME=vivid
DISTRIB_DESCRIPTION="Ubuntu 15.04"
>> lsusb
Bus 003 Device 002: ID 8087:8000 Intel Corp.
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 006: ID 048d:8350 Integrated Technology Express, Inc.
Bus 001 Device 005: ID 8087:07dc Intel Corp.
Bus 001 Device 004: ID 04f2:b40f Chicony Electronics Co., Ltd
Bus 001 Device 003: ID 04f3:0303 Elan Microelectronics Corp.
Bus 001 Device 002: ID 0bda:0129 Realtek Semiconductor Corp. RTS5129 Card Reader Controller
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
>> lspci -k -nn | grep -A 3 -i net
01:00.0 Network controller [0280]: Intel Corporation Wireless 7260 [8086:08b2] (rev 6b)
Subsystem: Intel Corporation Wireless-N 7260 [8086:c262]
Kernel driver in use: iwlwifi
>> sudo lshw -C network
*-network
description: Interface réseau sans fil
produit: Wireless 7260
fabriquant: Intel Corporation
identifiant matériel: 0
information bus: pci@0000:01:00.0
nom logique: wlan0
version: 6b
numéro de série: e8:b1:fc:0c:54:b3
bits: 64 bits
horloge: 33MHz
fonctionnalités: pm msi pciexpress bus_master cap_list ethernet physical wireless
configuration: broadcast=yes driver=iwlwifi driverversion=3.19.0-15-generic firmware=25.15.12.0 ip=192.168.25.76 latency=0 link=yes multicast=yes wireless=IEEE 802.11bgn
ressources: irq:45 mémoire:b0400000-b0401fff
>> lsmod
Module Size Used by
ctr 16384 1
ccm 20480 1
binfmt_misc 20480 1
rfcomm 69632 8
bnep 20480 2
rtsx_usb_ms 20480 0
memstick 20480 1 rtsx_usb_ms
hid_sensor_magn_3d 16384 0
hid_sensor_incl_3d 16384 0
hid_sensor_rotation 16384 0
hid_sensor_accel_3d 16384 0
hid_sensor_gyro_3d 16384 0
hid_sensor_als 16384 0
hid_sensor_trigger 16384 12 hid_sensor_gyro_3d,hid_sensor_incl_3d,hid_sensor_accel_3d,hid_sensor_rotation,hid_sensor_als,hid_sensor_magn_3d
industrialio_triggered_buffer 16384 6 hid_sensor_gyro_3d,hid_sensor_incl_3d,hid_sensor_accel_3d,hid_sensor_rotation,hid_sensor_als,hid_sensor_magn_3d
kfifo_buf 16384 1 industrialio_triggered_buffer
industrialio 57344 9 hid_sensor_trigger,hid_sensor_gyro_3d,industrialio_triggered_buffer,hid_sensor_incl_3d,hid_sensor_accel_3d,hid_sensor_rotation,hid_sensor_als,kfifo_buf,hid_sensor_magn_3d
hid_sensor_iio_common 16384 6 hid_sensor_gyro_3d,hid_sensor_incl_3d,hid_sensor_accel_3d,hid_sensor_rotation,hid_sensor_als,hid_sensor_magn_3d
hid_multitouch 20480 0
hid_sensor_hub 20480 8 hid_sensor_trigger,hid_sensor_gyro_3d,hid_sensor_incl_3d,hid_sensor_accel_3d,hid_sensor_rotation,hid_sensor_als,hid_sensor_magn_3d,hid_sensor_iio_common
uvcvideo 90112 0
videobuf2_vmalloc 16384 1 uvcvideo
videobuf2_memops 16384 1 videobuf2_vmalloc
videobuf2_core 49152 1 uvcvideo
v4l2_common 16384 1 videobuf2_core
videodev 159744 3 uvcvideo,v4l2_common,videobuf2_core
usbhid 53248 0
media 24576 2 uvcvideo,videodev
btusb 32768 0
bluetooth 491520 22 bnep,btusb,rfcomm
arc4 16384 2
snd_hda_codec_hdmi 53248 1
joydev 20480 0
intel_rapl 20480 0
iosf_mbi 16384 1 intel_rapl
x86_pkg_temp_thermal 16384 0
intel_powerclamp 20480 0
coretemp 16384 0
kvm 483328 0
iwlmvm 278528 0
mac80211 720896 1 iwlmvm
crct10dif_pclmul 16384 0
crc32_pclmul 16384 0
ghash_clmulni_intel 16384 0
snd_hda_codec_realtek 86016 1
aesni_intel 172032 3
snd_hda_codec_generic 69632 1 snd_hda_codec_realtek
iwlwifi 196608 1 iwlmvm
aes_x86_64 20480 1 aesni_intel
lrw 16384 1 aesni_intel
i915 1052672 7
gf128mul 16384 1 lrw
cfg80211 540672 3 iwlwifi,mac80211,iwlmvm
glue_helper 16384 1 aesni_intel
ablk_helper 16384 1 aesni_intel
cryptd 20480 3 ghash_clmulni_intel,aesni_intel,ablk_helper
snd_soc_rt5640 94208 0
snd_soc_rl6231 16384 1 snd_soc_rt5640
snd_hda_intel 32768 7
snd_hda_controller 32768 1 snd_hda_intel
shpchp 40960 0
snd_hda_codec 143360 5 snd_hda_codec_realtek,snd_hda_codec_hdmi,snd_hda_codec_generic,snd_hda_intel,snd_hda_controller
snd_soc_core 196608 1 snd_soc_rt5640
snd_compress 20480 1 snd_soc_core
mei_me 20480 0
snd_hwdep 20480 1 snd_hda_codec
snd_pcm_dmaengine 16384 1 snd_soc_core
serio_raw 16384 0
mei 90112 1 mei_me
snd_pcm 106496 8 snd_soc_rt5640,snd_soc_core,snd_hda_codec_hdmi,snd_hda_codec,snd_hda_intel,snd_hda_controller,snd_pcm_dmaengine
snd_seq_midi 16384 0
lpc_ich 24576 0
snd_seq_midi_event 16384 1 snd_seq_midi
snd_rawmidi 32768 1 snd_seq_midi
snd_seq 69632 2 snd_seq_midi_event,snd_seq_midi
drm_kms_helper 122880 1 i915
snd_seq_device 16384 3 snd_seq,snd_rawmidi,snd_seq_midi
drm 344064 6 i915,drm_kms_helper
snd_timer 32768 2 snd_pcm,snd_seq
i2c_algo_bit 16384 1 i915
snd 90112 26 snd_hda_codec_realtek,snd_soc_core,snd_hwdep,snd_timer,snd_hda_codec_hdmi,snd_pcm,snd_seq,snd_rawmidi,snd_hda_codec_generic,snd_hda_codec,snd_hda_intel,snd_seq_device,snd_compress
ideapad_laptop 20480 0
soundcore 16384 2 snd,snd_hda_codec
sparse_keymap 16384 1 ideapad_laptop
i2c_hid 20480 0
hid 110592 4 i2c_hid,hid_multitouch,hid_sensor_hub,usbhid
video 20480 1 i915
dw_dmac 16384 0
dw_dmac_core 24576 1 dw_dmac
snd_soc_sst_acpi 16384 0
8250_dw 16384 0
i2c_designware_platform 16384 0
spi_pxa2xx_platform 24576 0
i2c_designware_core 16384 1 i2c_designware_platform
soc_button_array 16384 0
mac_hid 16384 0
parport_pc 32768 0
ppdev 20480 0
lp 20480 0
parport 45056 3 lp,ppdev,parport_pc
autofs4 40960 2
rtsx_usb_sdmmc 28672 0
rtsx_usb 24576 2 rtsx_usb_sdmmc,rtsx_usb_ms
psmouse 118784 0
ahci 36864 1
libahci 32768 1 ahci
sdhci_acpi 16384 0
sdhci 45056 1 sdhci_acpi
[/code]
[code]
>> iwconfig
wlan0 IEEE 802.11bgn ESSID:"GVT-947C"
Mode:Managed Frequency:2.462 GHz Access Point: 00:0C:C3:3B:94:7C
Bit Rate=1 Mb/s Tx-Power=22 dBm
Retry short limit:7 RTS thr:off Fragment thr:off
Power Management:on
Link Quality=45/70 Signal level=-65 dBm
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
Tx excessive retries:13 Invalid misc:87 Missed beacon:0
>> ifconfig -a
lo Link encap:Boucle locale
inet adr:127.0.0.1 Masque:255.0.0.0
adr inet6: ::1/128 Scope:Hôte
UP LOOPBACK RUNNING MTU:65536 Metric:1
Packets reçus:6898 erreurs:0 :0 overruns:0 frame:0
TX packets:6898 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 lg file transmission:0
Octets reçus:626740 (626.7 KB) Octets transmis:626740 (626.7 KB)
wlan0 Link encap:Ethernet HWaddr e8:b1:fc:0c:54:b3
inet adr:192.168.25.76 Bcast:192.168.25.255 Masque:255.255.255.0
adr inet6: fe80::eab1:fcff:fe0c:54b3/64 Scope:Lien
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
Packets reçus:200288 erreurs:0 :0 overruns:0 frame:0
TX packets:139328 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 lg file transmission:1000
Octets reçus:207651439 (207.6 MB) Octets transmis:19177032 (19.1 MB)
>> sudo iwlist scan
wlan0 Scan completed :
Cell 01 - Address: 00:0C:C3:3B:94:7C
Channel:11
Frequency:2.462 GHz (Channel 11)
Quality=48/70 Signal level=-62 dBm
Encryption key:on
ESSID:"GVT-947C"
Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 11 Mb/s; 18 Mb/s
24 Mb/s; 36 Mb/s; 54 Mb/s
Bit Rates:6 Mb/s; 9 Mb/s; 12 Mb/s; 48 Mb/s
Mode:Master
Extra:tsf=0000000de3b507a8
Extra: Last beacon: 26572ms ago
IE: Unknown: 00084756542D39343743
IE: Unknown: 010882848B962430486C
IE: Unknown: 03010B
IE: Unknown: 0706425220010D14
IE: Unknown: 2A0106
IE: Unknown: 2F0106
IE: IEEE 802.11i/WPA2 Version 1
Group Cipher : TKIP
Pairwise Ciphers (2) : CCMP TKIP
Authentication Suites (1) : PSK
IE: Unknown: 32040C121860
IE: Unknown: 0B0508007A0000
IE: Unknown: 2D1ABC1817FFFF000000000000000000000000000000000000000000
IE: Unknown: 3D160B001700000000000000000000000000000000000000
IE: Unknown: 7F03000008
IE: Unknown: DD800050F204104A0001101044000102103B000103104700107A100A47716E8627B12CA6C7656292D41021000842726F6164636F6D1023000842726F6164636F6D1024000631323334353610420004313233341054000800060050F20400011011000A42726F6164636F6D415010080002200C103C0001011049000600372A000120
IE: Unknown: DD090010180208040C0000
IE: Unknown: DD180050F2020101800003A4000027A4000042435E0062322F00
>> uname -r -m
3.19.0-15-generic x86_64
>> cat /etc/network/interfaces
# interfaces(5) file used by ifup(8) and ifdown(8)
auto lo
iface lo inet loopback
>> nm-tool
>> sudo rfkill list
0: ideapad_wlan: Wireless LAN
Soft blocked: no
Hard blocked: no
1: ideapad_bluetooth: Bluetooth
Soft blocked: no
Hard blocked: no
2: phy0: Wireless LAN
Soft blocked: no
Hard blocked: no
3: hci0: Bluetooth
Soft blocked: no
Hard blocked: no
And as requested by spinxz in the comments below:
>> modinfo iwlwifi | grep 7260
firmware: iwlwifi-7260-10.ucode
>> dmesg | grep iwl
[ 2.303627] iwlwifi 0000:01:00.0: loaded firmware version 25.15.12.0 op_modeiwlmvm
[ 2.333529] iwlwifi 0000:01:00.0: Detected Intel(R) Wireless N 7260, REV=0x144
[ 2.333581] iwlwifi 0000:01:00.0: L1 Disabled - LTR Enabled
[ 2.333802] iwlwifi 0000:01:00.0: L1 Disabled - LTR Enabled
[ 2.555400] ieee80211 phy0: Selected rate control algorithm 'iwl-mvm-rs'
[ 4.830019] iwlwifi 0000:01:00.0: L1 Disabled - LTR Enabled
[ 4.830243] iwlwifi 0000:01:00.0: L1 Disabled - LTR Enabled
[ 66.550674] iwlwifi 0000:01:00.0: L1 Disabled - LTR Enabled
[ 66.550900] iwlwifi 0000:01:00.0: L1 Disabled - LTR Enabled
Another request (by gertvdijk in the comments below):
>> apt-cache policy linux-firmware
linux-firmware:
Installé : 1.143
Candidat : 1.143
Table de version :
*** 1.143 0
500 http://fr.archive.ubuntu.com/ubuntu/ vivid/main amd64 Packages
100 /var/lib/dpkg/status
To answer another question of sinxz, here is the output of dmesg | grep iwl
after a disconnect and reconnect:
[ 2.303627] iwlwifi 0000:01:00.0: loaded firmware version 25.15.12.0 op_mode iwlmvm
[ 2.333529] iwlwifi 0000:01:00.0: Detected Intel(R) Wireless N 7260, REV=0x144
[ 2.333581] iwlwifi 0000:01:00.0: L1 Disabled - LTR Enabled
[ 2.333802] iwlwifi 0000:01:00.0: L1 Disabled - LTR Enabled
[ 2.555400] ieee80211 phy0: Selected rate control algorithm 'iwl-mvm-rs'
[ 4.830019] iwlwifi 0000:01:00.0: L1 Disabled - LTR Enabled
[ 4.830243] iwlwifi 0000:01:00.0: L1 Disabled - LTR Enabled
[ 66.550674] iwlwifi 0000:01:00.0: L1 Disabled - LTR Enabled
[ 66.550900] iwlwifi 0000:01:00.0: L1 Disabled - LTR Enabled
[ 2212.567922] iwlwifi 0000:01:00.0: L1 Disabled - LTR Enabled
[ 2212.568146] iwlwifi 0000:01:00.0: L1 Disabled - LTR Enabled
Edit: I also posted this question on the official French Ubuntu forum (here), and a user there made remarks that raise two questions:
- Is it possible that power management was always off on my previous version of Ubuntu (14.10)?
Is it normal that there is a file iwlwifi.conf in /etc/modprobe.d with the following content?
# /etc/modprobe.d/iwlwifi.conf
# iwlwifi will dyamically load either iwldvm or iwlmvm depending on the
# microcode file installed on the system. When removing iwlwifi, first
# remove the iwl?vm module and then iwlwifi.
remove iwlwifi \
(/sbin/lsmod | grep -o -e ^iwlmvm -e ^iwldvm -e ^iwlwifi | xargs/sbin/rmmod) \
&& /sbin/modprobe -r mac80211
Edit 2: It seems that my problem could now be completely solved. Let me make a few clarifications: the "instability" of my connection can be summed up by two "symptoms":
- Slow rates (concretely, max download speed at around 150Kb/s instead of 1Mb/s when it worked properly)
- "Effective disconnection" very frequently (every 30 seconds, say). What I mean by that is that the connection is not working at all, but the wifi does not "officially" disconnect. It comes back after waiting a few seconds (10 to 20s, say) or reconnecting to the network.
At first I thought that doing sudo iwconfig wlan0 power off
solved these issues completely, even if turning off power management is apparently not a "sustainable" solution (see spinxz's comments below). However I then realized that symptom #2 is still there, although much less frequently.
On the French Ubuntu forum (here), someone suggested I try to manually put the latest version of the version 12 firmware (downloadable here: https://wireless.wiki.kernel.org/_media/en/users/drivers/iwlwifi-7260-ucode-25.17.12.0.tgz) in /lib/firmware. I did that, and now the problem seems to be solved completely. To be honest, it might also have something to do with recent Ubuntu updates (they were a lot recently), I don't know. I am still not 100% certain the connection is back to working perfectly, or if it is only as good as the "power management off" solution, for example. I will let you know if that is the case.
Source: (StackOverflow)