Arch Linux

rd777

Member

Registered: 2013-05-21

Posts: 12

Wireless connection unstable and slow

Hello,
Lately I have been having problems with my wireless connection, as soon as i upgraded to the kernel 3.9.x problems started with netcfg. That's when I decided to move to netctl since the change was unavoidable anyway, however the main problem remained: the connection is established but after a while (sometimes 5 min, sometimes 2 hours) the speed drops drastically (0 bp/s) according to vnstat, nonetheless the connection is not dropped. I have narrowed the problem down to the following line from dmesg
[14679.955947] wlp7s0: AP c0:c1:c0:4e:9c:6d changed bandwidth, new config is 2452 MHz, width 2 (2442/0 MHz)
[15009.159019] wlp7s0: AP c0:c1:c0:4e:9c:6d changed bandwidth, new config is 2452 MHz, width 1 (2452/0 MHz)
Once this occurs, the rate drops to 0 and only a reboot or restarting the service for netctl would fix it. I then decided to try out wicd, however the problem remains the same.

$ uname -omr
3.9.5-1-ARCH x86_64 GNU/Linux

wicd 1.7.2.4 (bzr-r768) 
wireless (and wired) connection daemon.

$ systemctl | grep wireless
wicd.service                loaded active running   Wicd a wireless and wired network manager for Linux

 $ systemctl | grep wlp7s0
sys-devi...et-wlp7s0.device loaded active plugged   DWA-552 802.11n Xtreme N Desktop Adapter (rev A2)
sys-subs...es-wlp7s0.device loaded active plugged   DWA-552 802.11n Xtreme N Desktop Adapter (rev A2)

 $ lsmod | grep ath9k
ath9k                 100317  0 
ath9k_common            2096  1 ath9k
ath9k_hw              373214  2 ath9k_common,ath9k
ath                    15489  3 ath9k_common,ath9k,ath9k_hw
mac80211              487726  1 ath9k
cfg80211              452332  3 ath,ath9k,mac80211

 $ ip link
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT 
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: wlp7s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP mode DORMANT qlen 1000
    link/ether 00:18:e7:db:23:85 brd ff:ff:ff:ff:ff:ff

$ iwconfig
wlp7s0    IEEE 802.11bgn  ESSID:"netgear"  
          Mode:Managed  Frequency:2.452 GHz  Access Point: C0:C1:C0:4E:9C:6D   
          Bit Rate=78 Mb/s   Tx-Power=18 dBm   
          Retry  long limit:7   RTS thr:off   Fragment thr:off
          Power Management:off
          Link Quality=31/70  Signal level=-79 dBm  
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:1112  Invalid misc:740   Missed beacon:0

lo        no wireless extensions. 

 $  dmesg | grep wlp7s0
[13780.662014] IPv6: ADDRCONF(NETDEV_UP): wlp7s0: link is not ready
[13782.783957] wlp7s0: authenticate with c0:c1:c0:4e:9c:6d
[13782.801969] wlp7s0: send auth to c0:c1:c0:4e:9c:6d (try 1/3)
[13782.821644] wlp7s0: authenticated
[13782.823579] wlp7s0: associate with c0:c1:c0:4e:9c:6d (try 1/3)
[13782.886137] wlp7s0: RX AssocResp from c0:c1:c0:4e:9c:6d (capab=0x411 status=0 aid=2)
[13782.886217] wlp7s0: associated
[13782.886239] IPv6: ADDRCONF(NETDEV_CHANGE): wlp7s0: link becomes ready
[14679.955947] wlp7s0: AP c0:c1:c0:4e:9c:6d changed bandwidth, new config is 2452 MHz, width 2 (2442/0 MHz)
[15009.159019] wlp7s0: AP c0:c1:c0:4e:9c:6d changed bandwidth, new config is 2452 MHz, width 1 (2452/0 MHz)
 

Thank you again for your time and help!

PS: will post later what iwconfig and vnstat look like after the problem occurs without fixing it.
Ok. here's vnstat output when the problem occurs and here's the ip link output as well

$  vnstat -l -i wlp7s0
Monitoring wlp7s0...    (press CTRL-C to stop)

   rx:        0 kbit/s     2 p/s          tx:        0 kbit/s     0 p/s^C

$ ip link
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT 
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: wlp7s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP mode DORMANT qlen 1000
    link/ether 00:18:e7:db:23:85 brd ff:ff:ff:ff:ff:ff

Last edited by rd777 (2013-06-14 20:46:16)