我在 Windows 7 的三重启动中运行 (K)Ubuntu 12.10/12.04 并以无线方式访问互联网。这在大多数情况下都运行正常。有时在正常重启后，无线连接会消失。在 Ubuntu 中，它表现为网络管理器中显示“设备未就绪”，而在 Kubuntu 中，WLAN 接口在相应的 KDE 网络管理器小部件中显示为“不可用”。通常，当可用时，会显示我的无线连接的 SSID，然后我会自动连接到它。
此时，唯一能帮助我恢复无线连接的方法就是启动并退出 Windows 7，然后返回 (K)Ubuntu。但是，我希望能够在不依赖 Windows 7 的情况下修复该问题。
以下是我用于调试的一些相关命令输出：
user@user-desktop:~$ lspci -nnk | grep -iA2 net
02:00.0 Ethernet controller [0200]: Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller [10ec:8168] (rev 03)
Subsystem: Hewlett-Packard Company Device [103c:2a9c]
Kernel driver in use: r8169
--
04:00.0 Network controller [0280]: Ralink corp. RT3090 Wireless 802.11n 1T/1R PCIe [1814:3090]
Subsystem: Lite-On Communications Inc Device [11ad:6632]
Kernel driver in use: rt2800pci
user@user-desktop:~$ lsmod
Module Size Used by
parport_pc 32689 0
ppdev 17074 0
bnep 18141 2
binfmt_misc 17501 1
rfcomm 46620 0
bluetooth 209438 10 bnep,rfcomm
nvidia 9367981 38
arc4 12530 2
rt2800pci 18529 0
rt2800lib 58731 1 rt2800pci
crc_ccitt 12708 1 rt2800lib
rt2x00pci 14519 1 rt2800pci
snd_hda_codec_realtek 78147 1
rt2x00lib 54995 3 rt2800pci,rt2800lib,rt2x00pci
snd_hda_intel 33492 3
mac80211 535936 3 rt2800lib,rt2x00pci,rt2x00lib
snd_hda_codec 134213 2 snd_hda_codec_realtek,snd_hda_intel
coretemp 13401 0
snd_hwdep 17699 1 snd_hda_codec
gpio_ich 13384 0
cfg80211 206797 2 rt2x00lib,mac80211
snd_pcm 96668 2 snd_hda_intel,snd_hda_codec
kvm_intel 132760 0
snd_seq_midi 13325 0
snd_rawmidi 30513 1 snd_seq_midi
kvm 414111 1 kvm_intel
eeprom_93cx6 13345 1 rt2800pci
snd_seq_midi_event 14900 1 snd_seq_midi
snd_seq 61555 2 snd_seq_midi,snd_seq_midi_event
psmouse 100424 0
joydev 17458 0
lpc_ich 17062 0
i7core_edac 23572 0
mei 40691 0
snd_timer 29426 2 snd_pcm,snd_seq
snd_seq_device 14498 3 snd_seq_midi,snd_rawmidi,snd_seq
mac_hid 13206 0
serio_raw 13216 0
lp 17760 0
snd 78921 15 snd_hda_codec_realtek,snd_hda_intel,snd_hda_codec,snd_hwdep,snd_pcm,snd_rawmidi,snd_seq,snd_timer,snd_seq_device
edac_core 52452 3 i7core_edac
parport 46346 3 parport_pc,ppdev,lp
wmi 19071 0
microcode 22804 0
soundcore 15048 1 snd
snd_page_alloc 18485 2 snd_hda_intel,snd_pcm
hid_sony 12795 0
hid_generic 12541 0
usb_storage 48839 0
usbhid 46987 0
hid 100411 3 hid_sony,hid_generic,usbhid
firewire_ohci 40402 0
firewire_core 64369 1 firewire_ohci
crc_itu_t 12708 1 firewire_core
ahci 25721 2
r8169 61671 0
libahci 31192 1 ahci
user@user-desktop:~$ ifconfig -a
eth0 Link encap:Ethernet HWaddr aa:aa:aa:aa:aa:aa
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)
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:16436 Metric:1
RX packets:18 errors:0 dropped:0 overruns:0 frame:0
TX packets:18 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:1284 (1.2 KB) TX bytes:1284 (1.2 KB)
wlan0 Link encap:Ethernet HWaddr aa:aa:aa:aa:aa:aa
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)
user@user-desktop:~$ iwconfig
eth0 no wireless extensions.
lo no wireless extensions.
wlan0 IEEE 802.11bgn ESSID:off/any
Mode:Managed Access Point: Not-Associated Tx-Power=0 dBm
Retry long limit:7 RTS thr:off Fragment thr:off
Power Management:off
user@user-desktop:~$ rfkill list all
0: phy0: Wireless LAN
Soft blocked: no
Hard blocked: no
user@user-desktop:~$ sudo iwlist scan
eth0 Interface doesn't support scanning.
lo Interface doesn't support scanning.
wlan0 Interface doesn't support scanning : Network is down
user@user-desktop:~$ sudo lshw -C network
*-network
description: Ethernet interface
product: RTL8111/8168B PCI Express Gigabit Ethernet controller
vendor: Realtek Semiconductor Co., Ltd.
physical id: 0
bus info: pci@0000:02:00.0
logical name: eth0
version: 03
serial: aa:aa:aa:aa:aa:aa
size: 10Mbit/s
capacity: 1Gbit/s
width: 64 bits
clock: 33MHz
capabilities: pm msi pciexpress msix vpd bus_master cap_list rom ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd 1000bt 1000bt-fd autonegotiation
configuration: autonegotiation=on broadcast=yes driver=r8169 driverversion=2.3LK-NAPI duplex=half firmware=rtl_nic/rtl8168d-1.fw latency=0 link=no multicast=yes port=MII speed=10Mbit/s
resources: irq:45 ioport:d800(size=256) memory:fbdff000-fbdfffff memory:f6ffc000-f6ffffff memory:fbdc0000-fbddffff
*-network DISABLED
description: Wireless interface
product: RT3090 Wireless 802.11n 1T/1R PCIe
vendor: Ralink corp.
physical id: 0
bus info: pci@0000:04:00.0
logical name: wlan0
version: 00
serial: aa:aa:aa:aa:aa:aa
width: 32 bits
clock: 33MHz
capabilities: pm msi pciexpress bus_master cap_list ethernet physical wireless
configuration: broadcast=yes driver=rt2800pci driverversion=3.5.0-41-generic firmware=0.34 latency=0 link=no multicast=yes wireless=IEEE 802.11bgn
resources: irq:17 memory:fbff0000-fbffffff
我尝试使用以下方法手动启动无线网络：
sudo ifconfig wlan0 up
并得到以下输出：
SIOCSIFFLAGS: Input/output error
我发现系统日志中的以下条目很有趣（当启动导致无线无法正常工作时记录）：
Oct 15 19:29:57 user-desktop NetworkManager[1083]: <info> NetworkManager (version 0.9.6.0) is starting...
Oct 15 19:29:57 user-desktop NetworkManager[1083]: <info> Read config file /etc/NetworkManager/NetworkManager.conf
Oct 15 19:29:57 user-desktop NetworkManager[1083]: <info> WEXT support is enabled
...
Oct 15 19:29:57 user-desktop NetworkManager[1083]: SCPlugin-Ifupdown: init!
Oct 15 19:29:57 user-desktop NetworkManager[1083]: SCPlugin-Ifupdown: update_system_hostname
Oct 15 19:29:57 user-desktop NetworkManager[1083]: SCPluginIfupdown: management mode: managed
Oct 15 19:29:57 user-desktop NetworkManager[1083]: SCPlugin-Ifupdown: devices added (path: /sys/devices/pci0000:00/0000:00:1c.0/0000:02:00.0/net/eth0, iface: eth0)
Oct 15 19:29:57 user-desktop NetworkManager[1083]: SCPlugin-Ifupdown: device added (path: /sys/devices/pci0000:00/0000:00:1c.0/0000:02:00.0/net/eth0, iface: eth0): no ifupdown configuration found.
Oct 15 19:29:57 user-desktop NetworkManager[1083]: SCPlugin-Ifupdown: devices added (path: /sys/devices/pci0000:00/0000:00:1c.5/0000:04:00.0/net/wlan0, iface: wlan0)
Oct 15 19:29:57 user-desktop NetworkManager[1083]: SCPlugin-Ifupdown: device added (path: /sys/devices/pci0000:00/0000:00:1c.5/0000:04:00.0/net/wlan0, iface: wlan0): no ifupdown configuration found.
Oct 15 19:29:57 user-desktop NetworkManager[1083]: SCPlugin-Ifupdown: devices added (path: /sys/devices/virtual/net/lo, iface: lo)
Oct 15 19:29:57 user-desktop NetworkManager[1083]: SCPlugin-Ifupdown: device added (path: /sys/devices/virtual/net/lo, iface: lo): no ifupdown configuration found.
Oct 15 19:29:57 user-desktop NetworkManager[1083]: SCPlugin-Ifupdown: end _init.
Oct 15 19:29:57 user-desktop NetworkManager[1083]: <info> Loaded plugin ifupdown: (C) 2008 Canonical Ltd. To report bugs please use the NetworkManager mailing list.
Oct 15 19:29:57 user-desktop NetworkManager[1083]: <info> Loaded plugin keyfile: (c) 2007 - 2010 Red Hat, Inc. To report bugs please use the NetworkManager mailing list.
Oct 15 19:29:57 user-desktop NetworkManager[1083]: SCPlugin-Ifupdown: (18924336) ... get_connections.
Oct 15 19:29:57 user-desktop NetworkManager[1083]: SCPlugin-Ifupdown: (18924336) connections count: 0
Oct 15 19:29:57 user-desktop NetworkManager[1083]: keyfile: parsing xxx ...
Oct 15 19:29:57 user-desktop NetworkManager[1083]: keyfile: read connection 'xxx'
Oct 15 19:29:57 user-desktop NetworkManager[1083]: keyfile: parsing yyy ...
Oct 15 19:29:57 user-desktop NetworkManager[1083]: keyfile: read connection 'yyy'
Oct 15 19:29:57 user-desktop NetworkManager[1083]: keyfile: parsing zzz ...
Oct 15 19:29:57 user-desktop NetworkManager[1083]: keyfile: read connection 'zzz'
Oct 15 19:29:57 user-desktop NetworkManager[1083]: <info> modem-manager is now available
Oct 15 19:29:57 user-desktop NetworkManager[1083]: <info> monitoring kernel firmware directory '/lib/firmware'.
...
Oct 15 19:29:57 user-desktop NetworkManager[1083]: <info> found WiFi radio killswitch rfkill0 (at /sys/devices/pci0000:00/0000:00:1c.5/0000:04:00.0/ieee80211/phy0/rfkill0) (driver (unknown))
Oct 15 19:29:57 user-desktop NetworkManager[1083]: <info> WiFi enabled by radio killswitch; enabled by state file
Oct 15 19:29:57 user-desktop NetworkManager[1083]: <info> WWAN enabled by radio killswitch; enabled by state file
Oct 15 19:29:57 user-desktop NetworkManager[1083]: <info> WiMAX enabled by radio killswitch; enabled by state file
Oct 15 19:29:57 user-desktop NetworkManager[1083]: <info> Networking is enabled by state file
Oct 15 19:29:57 user-desktop NetworkManager[1083]: <warn> failed to allocate link cache: (-10) Operation not supported
Oct 15 19:29:57 user-desktop NetworkManager[1083]: <info> (eth0): carrier is OFF
Oct 15 19:29:57 user-desktop NetworkManager[1083]: <info> (eth0): new Ethernet device (driver: 'r8169' ifindex: 2)
Oct 15 19:29:57 user-desktop NetworkManager[1083]: <info> (eth0): exported as /org/freedesktop/NetworkManager/Devices/0
Oct 15 19:29:57 user-desktop NetworkManager[1083]: <info> (eth0): now managed
Oct 15 19:29:57 user-desktop NetworkManager[1083]: <info> (eth0): device state change: unmanaged -> unavailable (reason 'managed') [10 20 2]
Oct 15 19:29:57 user-desktop NetworkManager[1083]: <info> (eth0): bringing up device.
Oct 15 19:29:57 user-desktop cron[1172]: (CRON) STARTUP (fork ok)
Oct 15 19:29:57 user-desktop cron[1172]: (CRON) INFO (Running @reboot jobs)
Oct 15 19:29:57 user-desktop NetworkManager[1083]: <info> (eth0): preparing device.
Oct 15 19:29:57 user-desktop NetworkManager[1083]: <info> (eth0): deactivating device (reason 'managed') [2]
Oct 15 19:29:57 user-desktop NetworkManager[1083]: <info> (wlan0): using nl80211 for WiFi device control
Oct 15 19:29:57 user-desktop NetworkManager[1083]: <warn> (wlan0): driver supports Access Point (AP) mode
Oct 15 19:29:57 user-desktop NetworkManager[1083]: <info> (wlan0): new 802.11 WiFi device (driver: 'rt2800pci' ifindex: 3)
Oct 15 19:29:57 user-desktop NetworkManager[1083]: <info> (wlan0): exported as /org/freedesktop/NetworkManager/Devices/1
Oct 15 19:29:57 user-desktop NetworkManager[1083]: <info> (wlan0): now managed
Oct 15 19:29:57 user-desktop NetworkManager[1083]: <info> (wlan0): device state change: unmanaged -> unavailable (reason 'managed') [10 20 2]
Oct 15 19:29:57 user-desktop NetworkManager[1083]: <info> (wlan0): bringing up device.
...
Oct 15 19:29:59 user-desktop kernel: [ 31.050638] phy0 -> rt2800_wait_wpdma_ready: Error - WPDMA TX/RX busy [0x00000068].
...
Oct 15 19:30:00 user-desktop NetworkManager[1083]: <info> (wlan0): deactivating device (reason 'managed') [2]
...
Oct 15 19:30:00 user-desktop NetworkManager[1083]: <info> wpa_supplicant started
Oct 15 19:30:00 user-desktop kernel: [ 32.647940] phy0 -> rt2800_wait_wpdma_ready: Error - WPDMA TX/RX busy [0x00000068].
Oct 15 19:30:00 user-desktop kernel: [ 32.647949] phy0 -> rt2800pci_set_device_state: Error - Device failed to enter state 4 (-5).
Oct 15 19:30:00 user-desktop kernel: [ 32.648045] IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready
此外，每次我尝试启动 wlan0 时都会记录以下内容：
Oct 15 19:40:09 user-desktop kernel: [ 519.848361] phy0 -> rt2800_wait_wpdma_ready: Error - WPDMA TX/RX busy [0x00000068].
Oct 15 19:40:11 user-desktop kernel: [ 521.445718] phy0 -> rt2800_wait_wpdma_ready: Error - WPDMA TX/RX busy [0x00000068].
Oct 15 19:40:11 user-desktop kernel: [ 521.445724] phy0 -> rt2800pci_set_device_state: Error - Device failed to enter state 4 (-5).
观察结果：
1. 无线网络似乎有时会在重启时随机丢失（无论是在安装一些更新后还是在重启前没有安装任何更新时）
2. 当无线网络在其中一个（K）Ubuntu 中丢失时，启动另一个后无线网络也无法使用
3. 唯一能恢复无线网络的是重启 Windows 7 然后再恢复
在这种情况下，我该如何重新启用我的无线功能？
答案1
您是否曾尝试过手动将服务器重新添加到列表中？只需进入 Internet 选项卡并点击“编辑连接”。单击无线选项卡并点击添加。您必须知道服务器的名称和密码，但我相信您知道。如果这不起作用，也许可以尝试拔下 Wi-Fi 然后再插上，重新启动 Wi-Fi。