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Fedora Troubleshooting Wireless

Applicable to Fedora Versions

  • All Fedora Versions


Explanation of requirements.

  1. Fedora
  2. wireless card you would like to get working


How to test

Explanation troubleshooting basics and expectations.

  1. uname – tells you the version of the kernel you are running, useful to know when trying to get the wireless card working with Fedora
$ uname -a
Linux localhost.localdomain #1 SMP Mon Jul 7 20:46:03 EDT 2008 i686 i686 i386 GNU/Linux

2.dmesg – displays information that can be used to help troubleshoot faults.

$ dmesg
ADDRCONF(NETDEV_UP): wlan0: link is not ready
wlan0: Initial auth_alg=0
wlan0: authenticate with AP 00:0e:2e:c7:e5:7f
wlan0: RX authentication from 00:0e:2e:c7:e5:7f (alg=0 transaction=2 status=0)
wlan0: authenticated
wlan0: associate with AP 00:0e:2e:c7:e5:7f
wlan0: RX AssocResp from 00:0e:2e:c7:e5:7f (capab=0x431 status=0 aid=1)
wlan0: associated
wlan0: switched to long barker preamble (BSSID=00:0e:2e:c7:e5:7f)
ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready

3.lspci – displays more detailed information about the hardware of your wireless card, the following command will also tell you which kernel module is being used.

$ /sbin/lspci -v

02:00.0 Network controller: RaLink RT2561/RT61 802.11g PCI
        Subsystem: RaLink EW-7108PCg
        Flags: bus master, slow devsel, latency 64, IRQ 11
        Memory at 34000000 (32-bit, non-prefetchable) [size=32K]
        Kernel driver in use: rt61pci
        Kernel modules: rt61pci

4.Modinfo – displays information about the version of the kernel module used to make your wireless card work along with the name of the firmware file, replace rt61pci with the results of the previous lspci -v command for you card

$ modinfo rt61pci
filename:       /lib/modules/
license:        GPL
firmware:       rt2661.bin
firmware:       rt2561s.bin
firmware:       rt2561.bin
description:    Ralink RT61 PCI & PCMCIA Wireless LAN driver.
version:        2.1.4
srcversion:     B24486EDEB73036BAEB0438
alias:          pci:v00001814d00000401sv*sd*bc*sc*i*
alias:          pci:v00001814d00000302sv*sd*bc*sc*i*
alias:          pci:v00001814d00000301sv*sd*bc*sc*i*
depends:        rt2x00lib,rt2x00pci,crc-itu-t,eeprom_93cx6
vermagic: SMP mod_unload 686 4KSTACKS

5.ifconfig – gives you detailed information about the network interfaces on your machine.

$ ifconfig -a
lo        Link encap:Local Loopback  
          inet addr:  Mask:
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:3153 errors:0 dropped:0 overruns:0 frame:0
          TX packets:3153 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:2921024 (2.7 MiB)  TX bytes:2921024 (2.7 MiB)

wlan0     Link encap:Ethernet  HWaddr 00:0E:2E:C7:FE:49  
          inet addr:  Bcast:  Mask:
          inet6 addr: fe80::20e:2eff:fec7:fe49/64 Scope:Link
          RX packets:56 errors:0 dropped:0 overruns:0 frame:0
          TX packets:91 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:13650 (13.3 KiB)  TX bytes:12859 (12.5 KiB)

wmaster0  Link encap:UNSPEC  HWaddr 00-0E-2E-C7-FE-49-78-07-00-00-00-00-00-00-00-00  
          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)

6.iwconfig – tells you about your wireless card

$ iwconfig
lo        no wireless extensions.

wmaster0  no wireless extensions.

wlan0     IEEE 802.11g  ESSID:"default"  
          Mode:Managed  Frequency:2.462 GHz  Access Point: 00:0E:2E:C7:E5:7F   
          Bit Rate=54 Mb/s   Tx-Power=27 dBm   
          Retry min limit:7   RTS thr:off   Fragment thr=2352 B   
          Link Quality=72/100  Signal level=-48 dBm  
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0

7.iwlist – Get more detailed wireless information from a wireless interface.

$ su -c 'iwlist wlan0 scan'
wlan0     Scan completed :
          Cell 01 - Address: 00:0E:2E:C7:E5:7F
                    Frequency:2.462 GHz (Channel 11)
                    Quality=52/100  Signal level=-46 dBm  
                    Encryption key:on
                    IE: WPA Version 1
                        Group Cipher : TKIP
                        Pairwise Ciphers (1) : TKIP
                        Authentication Suites (1) : PSK
                    Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 11 Mb/s; 6 Mb/s
                              9 Mb/s; 12 Mb/s; 18 Mb/s; 24 Mb/s; 36 Mb/s
                              48 Mb/s; 54 Mb/s

Common problems and fixes

Describe common problems here, include links to known common problems if on another site

Wireless stopped working after I updated the kernelBoot into the previous kernel
I need to boot into more than the previous kernelIncrease the number of kernels that Fedora keeps before removing the oldest one by editing /etc/yum.conf and increasing the “installonly_limit=2” line to the number of kernels you wish to keep
I need wireless to work after the machine is started and before I loginThis feature is on the To Do list, when implemented In NetworkManager, tick the box System Settings
I need to setup a Static IP AddressIn NetworkManager, Edit the connection and specify a Static IP address
 NetworkManager fails to see wireless networks with Intel 3945 chipsetsRead the Fedora 8 common bugs wiki article.
The wireless device is not working correctlyCheck Network Configuration Edit Tick Controlled by NetworkManager, Untick Activate device when Computer Starts
LAN connectivity was fine, Speed Browsing from Windos XP was fine, Fedora 8 x86_64 with firefox, slow in opening web pages (download speed 6k ~12k) yum install (any updates ) would fail and start slow with alternative sites and then pickup download speed.disable ipv6 on firefox (open firefox and on the URL bar type “about:config” search for ipv6, change the value disbale IPV6 to “TRUE”)

edit /etc/sysctl.conf and add the following lines

#Control TCP Windows Scalling
net.ipv4.tcp_window_scaling = 0

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