3

I have two open WiFi networks in my building, call them A and B. I have lived here for over two years and they have always worked, but now (after being away for a while) I've been experiencing problems that I can't diagnose.

The problem is that after a while (sometimes 5 min, sometimes an hour) the network I'm connected to stops and then I have to change to the other one. And this goes on indefinitely, where I have to keep changing between networks A and B.

I'm pretty sure this is a problem with my computer, because when I connect to the same networks with my phone they work perfectly. Also I have called the IT people here and they assured me that the network is working fine. The thing is, this doesn't happen with other networks (that I've noticed).

The problem is, I don't even know how to diagnose the problem, let alone fix it. I've tried resetting these connections and restarting the computer, I've installed all the updates (because maybe it's a bug on network manager introduced by an earlier update...).

How do I go about diagnosing this problem (and subsequently solving it)?

PS: I have Arch Linux (up-to-date) on a Samsung 9 laptop.

PS2: When issuing ping 8.8.8.8 I get normal results for a while and eventually it prints out:

From 000.00.000.00 icmp_seq=1311 Destination Host Unreachable

where the zeros above represent my current IP.

EDIT:

Pinging the router's IP gives me exactly the same thing as pinging 8.8.8.8: Destination Host Unreachable.

This is the output of Network Manager using journalctl --boot _SYSTEMD_UNIT=NetworkManager.service. Apparently the interesting line is the line with the warning and the message connection disconnected (reason 6). I have also caught a reason -3 there once or twice.

I've also tried this suggestion here but it didn't work.

EDIT 2:

Adding the output of lsusb:

Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 005: ID 04e8:7301 Samsung Electronics Co., Ltd 
Bus 001 Device 004: ID 2232:1083 Silicon Motion 
Bus 001 Device 003: ID 8087:0a2b Intel Corp. 
Bus 001 Device 002: ID 1ea7:0064 SHARKOON Technologies GmbH 
Bus 001 Device 007: ID 22b8:2e24 Motorola PCS 
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

Adding the output of iwconfig when connecting through my phone's USB:

wlp1s0    IEEE 802.11  ESSID:off/any                                                                                                                                         
          Mode:Managed  Access Point: Not-Associated   Tx-Power=off                                                                                                          
          Retry short limit:7   RTS thr:off   Fragment thr:off                                                                                                               
          Power Management:off                                                                                                                                               

vpn0      no wireless extensions.                                                                                                                                            

enp0s20f0u1  no wireless extensions.                                                                                                                                         

lo        no wireless extensions.    

Adding the output of iwconfig when connecting through one of the WiFis while it's working (the output of the other WiFi is almost exactly the same):

wlp1s0    IEEE 802.11  ESSID:"AP A"
          Mode:Managed  Frequency:5.785 GHz  Access Point: 24:DE:C6:D8:5E:11   
          Bit Rate=180 Mb/s   Tx-Power=22 dBm   
          Retry short limit:7   RTS thr:off   Fragment thr:off
          Power Management:off
          Link Quality=38/70  Signal level=-72 dBm  
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0

lo        no wireless extensions.

The output of iwconfig when the WiFi isn't working is this:

wlp1s0    IEEE 802.11  ESSID:"AP A"
          Mode:Managed  Frequency:2.412 GHz  Access Point: 24:DE:C6:D8:5E:01
          Bit Rate=144.4 Mb/s   Tx-Power=22 dBm
          Retry short limit:7   RTS thr:off   Fragment thr:off
          Power Management:off
          Link Quality=58/70  Signal level=-52 dBm
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:4  Invalid misc:2   Missed beacon:0

lo        no wireless extensions.

Adding the output of lspci just in case:

00:00.0 Host bridge: Intel Corporation Xeon E3-1200 v6/7th Gen Core Processor Host Bridge/DRAM Registers (rev 02)
00:02.0 VGA compatible controller: Intel Corporation HD Graphics 620 (rev 02)
00:04.0 Signal processing controller: Intel Corporation Xeon E3-1200 v5/E3-1500 v5/6th Gen Core Processor Thermal Subsystem (rev 02)
00:14.0 USB controller: Intel Corporation Sunrise Point-LP USB 3.0 xHCI Controller (rev 21)
00:14.2 Signal processing controller: Intel Corporation Sunrise Point-LP Thermal subsystem (rev 21)
00:15.0 Signal processing controller: Intel Corporation Sunrise Point-LP Serial IO I2C Controller #0 (rev 21)
00:16.0 Communication controller: Intel Corporation Sunrise Point-LP CSME HECI #1 (rev 21)
00:17.0 SATA controller: Intel Corporation Sunrise Point-LP SATA Controller [AHCI mode] (rev 21)
00:1c.0 PCI bridge: Intel Corporation Sunrise Point-LP PCI Express Root Port #3 (rev f1)
00:1f.0 ISA bridge: Intel Corporation Sunrise Point-LP LPC Controller (rev 21)
00:1f.2 Memory controller: Intel Corporation Sunrise Point-LP PMC (rev 21)
00:1f.3 Audio device: Intel Corporation Sunrise Point-LP HD Audio (rev 21)
00:1f.4 SMBus: Intel Corporation Sunrise Point-LP SMBus (rev 21)
01:00.0 Network controller: Intel Corporation Wireless 8265 / 8275 (rev 78)

Output from dmesg|grep -i wlp1:

[13075.528210] wlp1s0: send auth to 24:de:c6:d8:5e:00 (try 1/3)
[13075.535068] wlp1s0: authenticated
[13075.536172] wlp1s0: associate with 24:de:c6:d8:5e:00 (try 1/3)
[13075.592422] wlp1s0: RX ReassocResp from 24:de:c6:d8:5e:00 (capab=0x431 status=0 aid=1)                                                                                   
[13075.595240] wlp1s0: associated
[13615.742696] wlp1s0: deauthenticated from 24:de:c6:d8:5e:00 (Reason: 3=DEAUTH_LEAVING)                                                                                    
[13616.436651] wlp1s0: authenticate with 24:de:c6:d8:5e:10
[13616.447550] wlp1s0: send auth to 24:de:c6:d8:5e:10 (try 1/3)
[13616.461910] wlp1s0: authenticated
[13616.464910] wlp1s0: associate with 24:de:c6:d8:5e:10 (try 1/3)
[13616.467729] wlp1s0: RX AssocResp from 24:de:c6:d8:5e:10 (capab=0x411 status=0 aid=1)                                                                                     
[13616.469656] wlp1s0: associated
[13643.275011] wlp1s0: disconnect from AP 24:de:c6:d8:5e:10 for new auth to 24:de:c6:d8:5e:00                                                                               
[13643.294441] wlp1s0: authenticate with 24:de:c6:d8:5e:00
[13643.301633] wlp1s0: send auth to 24:de:c6:d8:5e:00 (try 1/3)
[13643.313799] wlp1s0: authenticated
[13643.314546] wlp1s0: associate with 24:de:c6:d8:5e:00 (try 1/3)
[13643.374560] wlp1s0: RX ReassocResp from 24:de:c6:d8:5e:00 (capab=0x431 status=0 aid=1)                                                                                   
[13643.376725] wlp1s0: associated
[13645.942816] wlp1s0: deauthenticated from 24:de:c6:d8:5e:00 (Reason: 3=DEAUTH_LEAVING)                                                                                    
[13647.663157] wlp1s0: authenticate with 24:de:c6:d8:5e:10
[13647.676612] wlp1s0: send auth to 24:de:c6:d8:5e:10 (try 1/3)
[13647.690727] wlp1s0: authenticated
[13647.694544] wlp1s0: associate with 24:de:c6:d8:5e:10 (try 1/3)
[13647.698082] wlp1s0: RX AssocResp from 24:de:c6:d8:5e:10 (capab=0x411 status=0 aid=1)                                                                                     
[13647.700552] wlp1s0: associated
[13668.363354] wlp1s0: disconnect from AP 24:de:c6:d8:5e:10 for new auth to 24:de:c6:d8:5e:00                                                                               
[13668.380676] wlp1s0: authenticate with 24:de:c6:d8:5e:00
[13668.391924] wlp1s0: send auth to 24:de:c6:d8:5e:00 (try 1/3)
[13668.404645] wlp1s0: authenticated
[13668.407694] wlp1s0: associate with 24:de:c6:d8:5e:00 (try 1/3)
[13668.466700] wlp1s0: RX ReassocResp from 24:de:c6:d8:5e:00 (capab=0x431 status=0 aid=1)                                                                                   
[13668.470190] wlp1s0: associated
[13749.720151] wlp1s0: deauthenticating from 24:de:c6:d8:5e:00 by local choice (Reason: 3=DEAUTH_LEAVING)                                                                   
[13749.747718] IPv6: ADDRCONF(NETDEV_UP): wlp1s0: link is not ready
[13749.777939] IPv6: ADDRCONF(NETDEV_UP): wlp1s0: link is not ready
[13752.236392] wlp1s0: authenticate with 24:de:c6:d8:5e:01
[13752.245562] wlp1s0: send auth to 24:de:c6:d8:5e:01 (try 1/3)
[13752.249108] wlp1s0: authenticated
[13752.250272] wlp1s0: associate with 24:de:c6:d8:5e:01 (try 1/3)
[13752.254149] wlp1s0: RX AssocResp from 24:de:c6:d8:5e:01 (capab=0x421 status=0 aid=1)                                                                                     
[13752.256603] wlp1s0: associated
[13752.258164] IPv6: ADDRCONF(NETDEV_CHANGE): wlp1s0: link becomes ready

EDIT 3

I just checked the output of iwconfig when the connection is down and apparently the only thing that changed was the frequency from 5 to 2.4 GHz. However, I have issued the same command while the network was working and with the output being 2.4 GHz as well. So I don't think that is the reason.

  • That notebook model is known to have loads of wifi problems. You also do not specify neither brand of the wifi nor the model, however, it looks like a realtek which is a messed up chip. On top of all these circunstances, you also probably are bound to have wifi interferences, and probably the infra-structure is overloaded. I pretty much have honest doubts that dealing and debugging the sum of all those situations is on-topic here. tip: add to the question the output of lsusb and iwconfig. – Rui F Ribeiro Jan 22 at 20:51
  • @RuiFRibeiro I wasn't really aware of the problems of NP900. But this laptop has worked well since I've bought it almost 2 years ago. So it would be weird that a factory hardware problem is just acting up now out of the blue. I added the outputs that you asked plus lspci and I see no Realtek there anywhere. Any thoughts? – TomCho Jan 22 at 21:58
  • Please add also an iwconfig when associated/connected to an AP, or ideally two iwconfig with the two different APs – Rui F Ribeiro Jan 22 at 22:06
  • (adding iwconfig when in both APs might be useful to see the signal strength) – Rui F Ribeiro Jan 23 at 12:53
  • What happens if you use wpa_supplicant and dhcpcd instead? – Werdck Jan 23 at 17:52
1

First thing I would look for are error-messages, in the kernel ring buffer, with dmesg. I would look for debug output of the WiFi hardware driver stack. I usually see Intel drivers reporting associated and dissociated events including reasons.

Destination Host Unreachable most often means there is no route to this destination. You can check routes with ip r. Also your ip addresses might be of interest: ip a. Manual pages for ip.

Get some more information and report back!

  • Thanks for the tips. Here's a pastebin of the output of dmesg|grep -i wlp1. Pardon my ignorance, but is this the keyword I should be looking for? Looking for wlan0 shows me nothing. – TomCho Jan 19 at 1:48
  • The keyword for your grep looks good and I can't find anything suspicious there. If you are using Network Manager you could look into its logs with this command journalctl --boot _SYSTEMD_UNIT=NetworkManager.service. – thomas Jan 19 at 13:25
  • Also try to ping your router (in ip r the IP address after via) while your connection (ping to 8.8.8.8) is not working. – thomas Jan 19 at 13:31
  • Pinging the router just gives me exactly the same thing as pinging 8.8.8.8: Destination Host Unreachable. This is the output of Network Manager. Apparently the interesting line is the line with the warning and the message connection disconnected (reason 6). I found this question with a similar error which I will investigate. – TomCho Jan 19 at 16:58
  • 1
    "reason 6: class2FrameFromNonAuthStation: Client attempted to transfer data before it was authenticated." (from wiki.ubuntuusers.de/WLAN/#Logbucheintraege-auswerten). From your log it looks like your where successfully authenticated and assosiated. Also you got reason 3 in your dmesg log, which states the access point is going offline. Maybe someone is running death attack in your neighborhood: en.wikipedia.org/wiki/Wi-Fi_deauthentication_attack . You could try to use the Wireshark packet sniffer to see if it's an deauth attack. – thomas Jan 19 at 18:31

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