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As the title says, my wifi suddenly drops to very low speeds every few minutes. It gets so slow it's like it's disconnected but my wifi indicator says I remain connected. I am very new to linux but I know the basics (using the terminal and such). I just have no idea how to debug it as I do with windows.

So I will provide some basic data and please request any additional information you need.

Laptop: Sony Vaio E-series: VPCEH18FA (Asian model, got it as a gift)

CPU: Intel Core i5-2410M @ 2.30 GHz

OS: Ubuntu 14.04 "Trusty"

Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 06)

Network controller: Qualcomm Atheros AR9285 Wireless Network Adapter (PCI-Express) (rev 01)

EDIT:

iwconfig:

eth0      no wireless extensions.

wlan0     IEEE 802.11bgn  ESSID:"BELL786"  
          Mode:Managed  Frequency:2.412 GHz  Access Point: D8:6C:E9:24:55:85   
          Bit Rate=65 Mb/s   Tx-Power=15 dBm   
          Retry short limit:7   RTS thr:off   Fragment thr:off
          Power Management:off
          Link Quality=64/70  Signal level=-46 dBm  
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:459   Missed beacon:0

lo        no wireless extensions.

cat /var/log/syslog: http://pastebin.com/NpSPg0AP

  • Can you edit your question to include the output of iwconfig and the output of cat /var/log/syslog – Dylan Mar 21 '15 at 2:42
1

This should be the answer by the end of trouble shooting. Just want to write here for formatting and length.

Ok a couple questions I have... You use network manager(default wireless connection program in Ubuntu) to pick network and enter password, correct? It appears as thought your AP Bell76 is the issue. It is sending Deauth packets to your wireless card which causes your card to gladly disconnect. The network-manager then automatically connects again until it receices the next Deauth packet. This is what causes the drop in wifi server I believe.

The line that causes me to think this is from your syslog as seen below.

Mar 20 21:29:57 bbpgrs-VPCEH18FA kernel: [ 8419.673299] wlan0: deauthenticating from d8:6c:e9:24:55:85 by local choice (Reason: 3=DEAUTH_LEAVING)

Reason code 3 means:

3   station is leaving (or has left) IBSS or ESS

So to me it seems to be that the router is sending a deauth packet. Now if it is a directed packet(only addressed to your MAC) or if it is a broadcast deauth(a deauth packet sent to everyone on the wire) I do not know. This could be caused by several things.

Do you live around other people or is your house out of range of any other wireless networks?

What router do you have?

EDIT

Something else I noticed is that your txpower is kinda low, don't know if it is because your card is only capable of 20 or if you set it like that. You might consider raising the TX power, this may help your signal but also may cause your wifi card to run hotter.

Try:

sudo iwconfig wlan0 txpower 30
| improve this answer | |
  • 1) Yes I do use the default manager, if you know better alternatives please advise. 2) My router is: (still looking for exact model). 3) ran the command successfully. Finally, thanks for the reply :) – bbpgrs Mar 21 '15 at 8:00
  • Also i am not out of range of my router, my windows installation get good signal. – bbpgrs Mar 21 '15 at 8:04
  • I use wpa_supplicant as it allows you to control every aspect of the connection, while it is a little more work than the GUI is but at least you can control everything. Here is a pretty good example. – Dylan Mar 21 '15 at 16:49
  • Thanks, I'll take a look at that. Also I'm not sure if my problem is fixed but my connection is certainly a bit more stable now. – bbpgrs Mar 21 '15 at 18:36
  • Awesome! Yeah that 10db difference in the txpower will make a big difference. – Dylan Mar 21 '15 at 18:38

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