Ubuntu – Wifi keeps on and off all all the time

wireless

I have a Acer travilmate. After installing Ubuntu and connecting to a wireless network, my Wifi keeps turning on and off all the time, I hardly could do anything

This is really annoying because it stop me doing anything , I hardly load a video or game.

Is there any way to fix this and just let the wifi work As is required ?

Result of lspci -nnk | grep -iA2 net :

lspci -nnk | grep -iA2 net
00:1f.3 SMBus [0c05]: Intel Corporation NM10/ICH7 Family SMBus Controller [8086:27da] (rev 02)
    Subsystem: Acer Incorporated [ALI] Device [1025:0110]
02:00.0 Ethernet controller [0200]: Marvell Technology Group Ltd. 88E8038 PCI-E Fast Ethernet Controller [11ab:4352] (rev 14)
    Subsystem: Acer Incorporated [ALI] Device [1025:0110]
    Kernel driver in use: sky2
03:00.0 Network controller [0280]: Intel Corporation PRO/Wireless 3945ABG [Golan] Network Connection [8086:4222] (rev 02)
    Subsystem: Intel Corporation PRO/Wireless 3945BG Network Connection [8086:1005]
    Kernel driver in use: iwl3945
0a:09.0 CardBus bridge [0607]: Texas Instruments PCIxx12 Cardbus Controller [104c:8039]

Result of lsmod :

lsmod
Module                  Size  Used by
parport_pc             31981  0 
ppdev                  17391  0 
bnep                   18893  2 
rfcomm                 53664  16 
btusb                  23443  0 
bluetooth             323622  22 bnep,btusb,rfcomm
coretemp               13195  0 
joydev                 17097  0 
acer_wmi               31735  0 
sparse_keymap          13708  1 acer_wmi
snd_hda_codec_si3054    12864  1 
snd_hda_codec_realtek    45592  1 
gspca_vc032x           31199  0 
gspca_main             27772  1 gspca_vc032x
videodev              107508  2 gspca_vc032x,gspca_main
snd_hda_intel          42658  3 
snd_hda_codec         164003  3 snd_hda_codec_realtek,snd_hda_codec_si3054,snd_hda_intel
arc4                   12536  2 
snd_hwdep              13272  1 snd_hda_codec
snd_pcm                89488  3 snd_hda_codec_si3054,snd_hda_codec,snd_hda_intel
iwl3945                63619  0 
snd_page_alloc         14230  2 snd_pcm,snd_hda_intel
microcode              18830  0 
iwlegacy               87971  1 iwl3945
i915                  589697  3 
snd_seq_midi           13132  0 
mac80211              513247  2 iwl3945,iwlegacy
snd_seq_midi_event     14475  1 snd_seq_midi
snd_rawmidi            25094  1 snd_seq_midi
psmouse                90642  0 
snd_seq                55383  2 snd_seq_midi_event,snd_seq_midi
pcmcia                 51368  0 
snd_seq_device         14137  3 snd_seq,snd_rawmidi,snd_seq_midi
cfg80211              401436  3 iwl3945,iwlegacy,mac80211
drm_kms_helper         46867  1 i915
serio_raw              13189  0 
snd_timer              24447  2 snd_pcm,snd_seq
drm                   242354  4 i915,drm_kms_helper
snd                    60790  17 snd_hda_codec_realtek,snd_hda_codec_si3054,snd_hwdep,snd_timer,snd_pcm,snd_seq,snd_rawmidi,snd_hda_codec,snd_hda_intel,snd_seq_device,snd_seq_midi
yenta_socket           40193  0 
soundcore              12600  1 snd
pcmcia_rsrc            18319  1 yenta_socket
tifm_7xx1              13163  0 
pcmcia_core            22328  3 pcmcia,pcmcia_rsrc,yenta_socket
i2c_algo_bit           13197  1 i915
lpc_ich                16864  0 
tifm_core              15040  1 tifm_7xx1
wmi                    18590  1 acer_wmi
video                  18777  2 i915,acer_wmi
mac_hid                13037  0 
lp                     13299  0 
parport                40795  3 lp,ppdev,parport_pc
hid_generic            12492  0 
usbhid                 47361  0 
hid                    87370  2 hid_generic,usbhid
sky2                   52910  0

Result of iwconfig :

iwconfig
wlan0     IEEE 802.11bg  ESSID:"Etisalat"  
          Mode:Managed  Frequency:2.412 GHz  Access Point: C8:D1:5E:5B:CB:2C   
          Bit Rate=54 Mb/s   Tx-Power=15 dBm   
          Retry  long limit:7   RTS thr:off   Fragment thr:off
          Power Management:off
          Link Quality=65/70  Signal level=-45 dBm  
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:2   Missed beacon:0
lo        no wireless extensions.
eth0      no wireless extensions.

Result of ifconfig -a :

ifconfig -a
eth0      Link encap:Ethernet  HWaddr 00:16:36:9b:da:24  
          UP BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)
          Interrupt:16 
lo        Link encap:Local Loopback  
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:65536  Metric:1
          RX packets:1545 errors:0 dropped:0 overruns:0 frame:0
          TX packets:1545 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:116454 (116.4 KB)  TX bytes:116454 (116.4 KB)
wlan0     Link encap:Ethernet  HWaddr 00:18:de:46:aa:77  
          inet addr:192.168.1.6  Bcast:192.168.1.255  Mask:255.255.255.0
          inet6 addr: fe80::218:deff:fe46:aa77/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:2512 errors:0 dropped:0 overruns:0 frame:0
          TX packets:2634 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:892621 (892.6 KB)  TX bytes:478504 (478.5 KB)

Result of sudo iwlist scan :

sudo iwlist scan
wlan0     Scan completed :
          Cell 01 - Address: C8:D1:5E:5B:CB:2C
                    Channel:1
                    Frequency:2.412 GHz (Channel 1)
                    Quality=60/70  Signal level=-50 dBm  
                    Encryption key:on
                    ESSID:"Etisalat"
                    Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 11 Mb/s; 9 Mb/s
                              18 Mb/s; 36 Mb/s; 54 Mb/s
                    Bit Rates:6 Mb/s; 12 Mb/s; 24 Mb/s; 48 Mb/s
                    Mode:Master
                    Extra:tsf=0000000fee9c2e01
                    Extra: Last beacon: 44ms ago
                    IE: Unknown: 000845746973616C6174
                    IE: Unknown: 010882848B961224486C
                    IE: Unknown: 030101
                    IE: Unknown: 2A0100
                    IE: Unknown: 32040C183060
                    IE: Unknown: 2D1A8C0103FFFF0000000000000000000000000000000C0000000000
                    IE: Unknown: 3D1601000700000000000000000000000000000000000000
                    IE: Unknown: 3E0100
                    IE: IEEE 802.11i/WPA2 Version 1
                        Group Cipher : CCMP
                        Pairwise Ciphers (1) : CCMP
                        Authentication Suites (1) : PSK
                    IE: Unknown: DD180050F2020101000003A4000027A4000042435E0062322F00
                    IE: Unknown: DD07000C4307000000
                    IE: Unknown: 0706454720010D10
lo        Interface doesn't support scanning.
eth0      Interface doesn't support scanning.

Result of cat/etc/resolv.conf :

cat/etc/resolv.conf
# Dynamic resolv.conf(5) file for glibc resolver(3) generated by resolvconf(8)
#     DO NOT EDIT THIS FILE BY HAND -- YOUR CHANGES WILL BE OVERWRITTENnameserver 127.0.1.1

Best Answer

Different Problems can cause this

Application errors, Driver problems, Hardware problems including overheat, Network Interferences, Network registration, Channel you selected etc.

First get rid of Interfering devices like mobile phones etc.

Go to Network Connections > Wireless > Edit and set it as automatically connect.

Check with power off the device.

sudo iwconfig [INTERFAE]wlan0 power off

[INTERFAE] may be wlan0 or eth0 (or 1,2,3, etc)

If not resolved.:

Install device drivers for wifi

sudo apt-get install collectd-core collectd-dev collectd-dbg collectd-utils

And change the applications

sudo apt-get install wicd-gtk wicd wicd-daemon wicd-curses wicd-cli

With Wicd, change the Channel to 6.

If not resolved yet Edit the question with including the results of lspci -nnk | grep -iA2 net, lsmod, iwconfig, ifconfig -a, sudo iwlist scan, cat /etc/resolv.conf. Someone with expert knowledge may help.

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