我已经在 2010 年中期的 Macbook Pro 上使用 Ubuntu 一年多了。我成功安装了 Broadcom 无线设备的专有驱动程序，从未遇到过任何 wifi 问题。
升级到 18.04 后，wifi 工作正常。然后，有一天，它就不行了。
iwconfig的结果如下：
enp0s10 no wireless extensions.
lo no wireless extensions.
ifconfig：
enp0s10: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 192.168.1.13 netmask 255.255.255.0 broadcast 192.168.1.255
inet6 fe80::53da:4624:3774:bd2c prefixlen 64 scopeid 0x20<link>
ether 00:25:4b:c3:b2:4a txqueuelen 1000 (Ethernet)
RX packets 27922 bytes 29137649 (29.1 MB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 21190 bytes 2564310 (2.5 MB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536
inet 127.0.0.1 netmask 255.0.0.0
inet6 ::1 prefixlen 128 scopeid 0x10<host>
loop txqueuelen 1000 (Local Loopback)
RX packets 2802 bytes 276338 (276.3 KB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 2802 bytes 276338 (276.3 KB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
sudo lsusb：
Bus 002 Device 003: ID 05ac:8403 Apple, Inc. Internal Memory Card Reader
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 004 Device 003: ID 05ac:8213 Apple, Inc. Bluetooth Host Controller
Bus 004 Device 002: ID 0a5c:4500 Broadcom Corp. BCM2046B1 USB 2.0 Hub (part of BCM2046 Bluetooth)
Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 001 Device 002: ID 05ac:8507 Apple, Inc. Built-in iSight
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 Device 003: ID 05ac:0236 Apple, Inc. Internal Keyboard/Trackpad (ANSI)
Bus 003 Device 002: ID 05ac:8242 Apple, Inc. Built-in IR Receiver
Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
sudp lshw -C 网络：
*-network
description: Ethernet interface
product: MCP79 Ethernet
vendor: NVIDIA Corporation
physical id: a
bus info: pci@0000:00:0a.0
logical name: enp0s10
version: b1
serial: 00:25:4b:c3:b2:4a
size: 100Mbit/s
capacity: 1Gbit/s
width: 32 bits
clock: 66MHz
capabilities: pm msi bus_master cap_list ethernet physical mii 10bt 10bt-fd 100bt 100bt-fd 1000bt-fd autonegotiation
configuration: autonegotiation=on broadcast=yes driver=forcedeth driverversion=0.64 duplex=full ip=192.168.1.13 latency=0 link=yes maxlatency=20 mingnt=1 multicast=yes port=MII speed=100Mbit/s
resources: irq:26 memory:d3586000-d3586fff ioport:21e0(size=8) memory:d3589000-d35890ff memory:d3589300-d358930f
sudo rfkill 列表：
0: hci0: Bluetooth
Soft blocked: no
Hard blocked: no
猫/等/网络/接口：
# interfaces(5) file used by ifup(8) and ifdown(8)
auto lo
iface lo inet loopback
猫/etc/netplan/*.yaml：
# Let NetworkManager manage all devices on this system
network:
version: 2
renderer: NetworkManager
sudo lspci-nn：
00:00.0 Host bridge [0600]: NVIDIA Corporation MCP79 Host Bridge [10de:0a82] (rev b1)
00:00.1 RAM memory [0500]: NVIDIA Corporation MCP79 Memory Controller [10de:0a88] (rev b1)
00:03.0 ISA bridge [0601]: NVIDIA Corporation MCP79 LPC Bridge [10de:0aae] (rev b3)
00:03.1 RAM memory [0500]: NVIDIA Corporation MCP79 Memory Controller [10de:0aa4] (rev b1)
00:03.2 SMBus [0c05]: NVIDIA Corporation MCP79 SMBus [10de:0aa2] (rev b1)
00:03.3 RAM memory [0500]: NVIDIA Corporation MCP79 Memory Controller [10de:0a89] (rev b1)
00:03.4 RAM memory [0500]: NVIDIA Corporation MCP79 Memory Controller [10de:0a98] (rev b1)
00:03.5 Co-processor [0b40]: NVIDIA Corporation MCP79 Co-processor [10de:0aa3] (rev b1)
00:04.0 USB controller [0c03]: NVIDIA Corporation MCP79 OHCI USB 1.1 Controller [10de:0aa5] (rev b1)
00:04.1 USB controller [0c03]: NVIDIA Corporation MCP79 EHCI USB 2.0 Controller [10de:0aa6] (rev b1)
00:06.0 USB controller [0c03]: NVIDIA Corporation MCP79 OHCI USB 1.1 Controller [10de:0aa7] (rev b1)
00:06.1 USB controller [0c03]: NVIDIA Corporation MCP79 EHCI USB 2.0 Controller [10de:0aa9] (rev b1)
00:08.0 Audio device [0403]: NVIDIA Corporation MCP79 High Definition Audio [10de:0ac0] (rev b1)
00:09.0 PCI bridge [0604]: NVIDIA Corporation MCP79 PCI Bridge [10de:0aab] (rev b1)
00:0a.0 Ethernet controller [0200]: NVIDIA Corporation MCP79 Ethernet [10de:0ab0] (rev b1)
00:0b.0 SATA controller [0106]: NVIDIA Corporation MCP79 AHCI Controller [10de:0ab9] (rev b1)
00:0c.0 PCI bridge [0604]: NVIDIA Corporation MCP79 PCI Express Bridge [10de:0ac4] (rev b1)
00:10.0 PCI bridge [0604]: NVIDIA Corporation MCP79 PCI Express Bridge [10de:0aa0] (rev b1)
00:15.0 PCI bridge [0604]: NVIDIA Corporation MCP79 PCI Express Bridge [10de:0ac6] (rev b1)
00:16.0 PCI bridge [0604]: NVIDIA Corporation MCP79 PCI Express Bridge [10de:0ac7] (rev b1)
03:00.0 VGA compatible controller [0300]: NVIDIA Corporation C79 [GeForce 9400M] [10de:0863] (rev b1)
05:00.0 FireWire (IEEE 1394) [0c00]: LSI Corporation FW643 [TrueFire] PCIe 1394b Controller [11c1:5901] (rev 07)
cat 无线信息.txt：
########## wireless info START ##########
Report from: 20 Nov 2019 19:40 PST -0800
Booted last: 20 Nov 2019 00:00 PST -0800
Script from: 22 Oct 2018 03:34 UTC +0000
##### release ###########################
Distributor ID: Ubuntu
Description: Ubuntu 18.04.3 LTS
Release: 18.04
Codename: bionic
##### kernel ############################
Linux 5.0.0-36-generic #39~18.04.1-Ubuntu SMP Tue Nov 12 11:09:50 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux
Parameters: ro, quiet, splash, vt.handoff=1
##### desktop ###########################
GNOME on Xorg
##### lspci #############################
00:0a.0 Ethernet controller [0200]: NVIDIA Corporation MCP79 Ethernet [10de:0ab0] (rev b1)
Subsystem: NVIDIA Corporation Apple iMac 9,1 [10de:cb79]
Kernel driver in use: forcedeth
##### lsusb #############################
Bus 002 Device 003: ID 05ac:8403 Apple, Inc. Internal Memory Card Reader
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 004 Device 003: ID 05ac:8213 Apple, Inc. Bluetooth Host Controller
Bus 004 Device 002: ID 0a5c:4500 Broadcom Corp. BCM2046B1 USB 2.0 Hub (part of BCM2046 Bluetooth)
Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 001 Device 002: ID 05ac:8507 Apple, Inc. Built-in iSight
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 Device 003: ID 05ac:0236 Apple, Inc. Internal Keyboard/Trackpad (ANSI)
Bus 003 Device 002: ID 05ac:8242 Apple, Inc. Built-in IR Receiver
Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
##### PCMCIA card info ##################
##### rfkill ############################
0: hci0: Bluetooth
Soft blocked: no
Hard blocked: no
##### secure boot #######################
This system doesn't support Secure Boot
##### lsmod #############################
mxm_wmi 16384 1 nouveau
wmi 28672 2 mxm_wmi,nouveau
##### interfaces ########################
[/etc/network/interfaces]
auto lo
iface lo inet loopback
##### ifconfig ##########################
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
link/loopback <MAC address> brd <MAC address>
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: enp0s10: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
link/ether <MAC 'enp0s10' [IF1]> brd <MAC address>
inet 192.168.1.13/24 brd 192.168.1.255 scope global dynamic noprefixroute enp0s10
valid_lft 82830sec preferred_lft 82830sec
inet6 fe80::53da:4624:3774:bd2c/64 scope link noprefixroute
valid_lft forever preferred_lft forever
3: tun0: <POINTOPOINT,MULTICAST,NOARP,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UNKNOWN group default qlen 100
link/none
inet 10.7.0.2/24 brd 10.7.0.255 scope global tun0
valid_lft forever preferred_lft forever
inet6 fe80::77f3:43f5:d857:222a/64 scope link stable-privacy
valid_lft forever preferred_lft forever
##### iwconfig ##########################
enp0s10 no wireless extensions.
tun0 no wireless extensions.
lo no wireless extensions.
##### route #############################
0.0.0.0/1 via 10.7.0.1 dev tun0
default via 192.168.1.1 dev enp0s10 proto dhcp metric 100
10.7.0.0/24 dev tun0 proto kernel scope link src 10.7.0.2
104.140.14.58 via 192.168.1.1 dev enp0s10
128.0.0.0/1 via 10.7.0.1 dev tun0
169.254.0.0/16 dev enp0s10 scope link metric 1000
192.168.1.0/24 dev enp0s10 proto kernel scope link src 192.168.1.13 metric 100
##### resolv.conf #######################
[777 root '/etc/resolv.conf' -> '../run/systemd/resolve/stub-resolv.conf']
nameserver 127.0.0.53
options edns0
##### network managers ##################
Installed:
NetworkManager
Running:
root 874 1 0 18:40 ? 00:00:00 /usr/sbin/NetworkManager --no-daemon
##### NetworkManager info ###############
GENERAL.DEVICE: enp0s10
GENERAL.TYPE: ethernet
GENERAL.NM-TYPE: NMDeviceEthernet
GENERAL.VENDOR: NVIDIA Corporation
GENERAL.PRODUCT: MCP79 Ethernet (Apple iMac 9,1)
GENERAL.DRIVER: forcedeth
GENERAL.DRIVER-VERSION: 0.64
GENERAL.FIRMWARE-VERSION: --
GENERAL.HWADDR: <MAC 'enp0s10' [IF1]>
GENERAL.MTU: 1500
GENERAL.STATE: 100 (connected)
GENERAL.REASON: 0 (No reason given)
GENERAL.UDI: /sys/devices/pci0000:00/0000:00:0a.0/net/enp0s10
GENERAL.IP-IFACE: enp0s10
GENERAL.IS-SOFTWARE: no
GENERAL.NM-MANAGED: yes
GENERAL.AUTOCONNECT: yes
GENERAL.FIRMWARE-MISSING: no
GENERAL.NM-PLUGIN-MISSING: no
GENERAL.PHYS-PORT-ID: --
GENERAL.CONNECTION: Wired connection 1
GENERAL.CON-UUID: c10bab60-1b82-3605-ba19-c237b90d8f1a
GENERAL.CON-PATH: /org/freedesktop/NetworkManager/ActiveConnection/1
GENERAL.METERED: no (guessed)
CAPABILITIES.CARRIER-DETECT: yes
CAPABILITIES.SPEED: 1000 Mb/s
CAPABILITIES.IS-SOFTWARE: no
CAPABILITIES.SRIOV: no
WIRED-PROPERTIES.CARRIER: on
IP4.ADDRESS[1]: 192.168.1.13/24
IP4.GATEWAY: 192.168.1.1
IP4.ROUTE[1]: dst = 0.0.0.0/0, nh = 192.168.1.1, mt = 100
IP4.ROUTE[2]: dst = 192.168.1.0/24, nh = 0.0.0.0, mt = 100
IP4.ROUTE[3]: dst = 169.254.0.0/16, nh = 0.0.0.0, mt = 1000
IP4.ROUTE[4]: dst = 104.140.14.58/32, nh = 192.168.1.1, mt = 0
IP4.DNS[1]: 192.168.1.1
DHCP4.OPTION[1]: requested_host_name = 1
DHCP4.OPTION[2]: requested_domain_search = 1
DHCP4.OPTION[3]: requested_time_offset = 1
DHCP4.OPTION[4]: requested_domain_name = 1
DHCP4.OPTION[5]: requested_rfc3442_classless_static_routes = 1
DHCP4.OPTION[6]: requested_broadcast_address = 1
DHCP4.OPTION[7]: requested_wpad = 1
DHCP4.OPTION[8]: requested_netbios_scope = 1
DHCP4.OPTION[9]: next_server = 0.0.0.0
DHCP4.OPTION[10]: broadcast_address = 192.168.1.255
DHCP4.OPTION[11]: dhcp_message_type = 5
DHCP4.OPTION[12]: requested_interface_mtu = 1
DHCP4.OPTION[13]: dhcp_lease_time = 86400
DHCP4.OPTION[14]: ip_address = 192.168.1.13
DHCP4.OPTION[15]: requested_subnet_mask = 1
DHCP4.OPTION[16]: subnet_mask = 255.255.255.0
DHCP4.OPTION[17]: requested_domain_name_servers = 1
DHCP4.OPTION[18]: routers = 192.168.1.1
DHCP4.OPTION[19]: expiry = 1574390435
DHCP4.OPTION[20]: requested_ntp_servers = 1
DHCP4.OPTION[21]: requested_netbios_name_servers = 1
DHCP4.OPTION[22]: domain_name_servers = 192.168.1.1
DHCP4.OPTION[23]: requested_ms_classless_static_routes = 1
DHCP4.OPTION[24]: requested_routers = 1
DHCP4.OPTION[25]: requested_static_routes = 1
DHCP4.OPTION[26]: network_number = 192.168.1.0
DHCP4.OPTION[27]: dhcp_server_identifier = 192.168.1.1
IP6.ADDRESS[1]: fe80::53da:4624:3774:bd2c/64
IP6.GATEWAY: --
IP6.ROUTE[1]: dst = ff00::/8, nh = ::, mt = 256, table=255
IP6.ROUTE[2]: dst = fe80::/64, nh = ::, mt = 256
IP6.ROUTE[3]: dst = fe80::/64, nh = ::, mt = 100
CONNECTIONS.AVAILABLE-CONNECTION-PATHS: /org/freedesktop/NetworkManager/Settings/{1}
CONNECTIONS.AVAILABLE-CONNECTIONS[1]: c10bab60-1b82-3605-ba19-c237b90d8f1a | Wired connection 1
GENERAL.DEVICE: tun0
GENERAL.TYPE: tun
GENERAL.NM-TYPE: NMDeviceTun
GENERAL.VENDOR: --
GENERAL.PRODUCT: --
GENERAL.DRIVER: tun
GENERAL.DRIVER-VERSION: 1.6
GENERAL.FIRMWARE-VERSION: --
GENERAL.HWADDR: (unknown)
GENERAL.MTU: 1500
GENERAL.STATE: 100 (connected)
GENERAL.REASON: 0 (No reason given)
GENERAL.UDI: /sys/devices/virtual/net/tun0
GENERAL.IP-IFACE: tun0
GENERAL.IS-SOFTWARE: yes
GENERAL.NM-MANAGED: yes
GENERAL.AUTOCONNECT: yes
GENERAL.FIRMWARE-MISSING: no
GENERAL.NM-PLUGIN-MISSING: no
GENERAL.PHYS-PORT-ID: --
GENERAL.CONNECTION: tun0
GENERAL.CON-UUID: 40a8300e-9fdd-4475-84e9-54752a5f8caa
GENERAL.CON-PATH: /org/freedesktop/NetworkManager/ActiveConnection/2
GENERAL.METERED: no (guessed)
CAPABILITIES.CARRIER-DETECT: no
CAPABILITIES.SPEED: unknown
CAPABILITIES.IS-SOFTWARE: yes
CAPABILITIES.SRIOV: no
IP4.ADDRESS[1]: 10.7.0.2/24
IP4.GATEWAY: --
IP4.ROUTE[1]: dst = 10.7.0.0/24, nh = 0.0.0.0, mt = 0
IP4.ROUTE[2]: dst = 0.0.0.0/1, nh = 10.7.0.1, mt = 0
IP4.ROUTE[3]: dst = 128.0.0.0/1, nh = 10.7.0.1, mt = 0
IP6.ADDRESS[1]: fe80::77f3:43f5:d857:222a/64
IP6.GATEWAY: --
IP6.ROUTE[1]: dst = ff00::/8, nh = ::, mt = 256, table=255
IP6.ROUTE[2]: dst = fe80::/64, nh = ::, mt = 256
CONNECTIONS.AVAILABLE-CONNECTION-PATHS: /org/freedesktop/NetworkManager/Settings/{2}
CONNECTIONS.AVAILABLE-CONNECTIONS[1]: 40a8300e-9fdd-4475-84e9-54752a5f8caa | tun0
##### NetworkManager.state ##############
[main]
NetworkingEnabled=true
WirelessEnabled=true
WWANEnabled=true
##### NetworkManager config #############
[[/etc/NetworkManager/conf.d/default-wifi-powersave-on.conf]]
[connection]
wifi.powersave = 3
[[/etc/NetworkManager/NetworkManager.conf]]
[main]
plugins=ifupdown,keyfile
[ifupdown]
managed=false
[device]
wifi.scan-rand-mac-address=no
[[/usr/lib/NetworkManager/conf.d/10-dns-resolved.conf]]
[main]
dns=systemd-resolved
[[/usr/lib/NetworkManager/conf.d/10-globally-managed-devices.conf]]
[keyfile]
unmanaged-devices=*,except:type:wifi,except:type:wwan
[[/usr/lib/NetworkManager/conf.d/20-connectivity-ubuntu.conf]]
[connectivity]
uri=http://connectivity-check.ubuntu.com/
[[/usr/lib/NetworkManager/conf.d/no-mac-addr-change.conf]]
[device-mac-addr-change-wifi]
match-device=driver:rtl8723bs,driver:rtl8189es,driver:r8188eu,driver:8188eu,driver:eagle_sdio,driver:wl
wifi.scan-rand-mac-address=no
wifi.cloned-mac-address=preserve
ethernet.cloned-mac-address=preserve
##### NetworkManager profiles ###########
##### Netplan config ####################
[/etc/netplan/01-network-manager-all.yaml]
network:
version: 2
renderer: NetworkManager
##### iw reg get ########################
Region: America/Los_Angeles (based on set time zone)
global
country 00: DFS-UNSET
(2402 - 2472 @ 40), (6, 20), (N/A)
(2457 - 2482 @ 20), (6, 20), (N/A), AUTO-BW, PASSIVE-SCAN
(2474 - 2494 @ 20), (6, 20), (N/A), NO-OFDM, PASSIVE-SCAN
(5170 - 5250 @ 80), (6, 20), (N/A), AUTO-BW, PASSIVE-SCAN
(5250 - 5330 @ 80), (6, 20), (0 ms), DFS, AUTO-BW, PASSIVE-SCAN
(5490 - 5730 @ 160), (6, 20), (0 ms), DFS, PASSIVE-SCAN
(5735 - 5835 @ 80), (6, 20), (N/A), PASSIVE-SCAN
(57240 - 63720 @ 2160), (N/A, 0), (N/A)
##### iwlist channels ###################
enp0s10 no frequency information.
tun0 no frequency information.
lo no frequency information.
##### iwlist scan #######################
Sorry, try again.
enp0s10 Interface doesn't support scanning.
tun0 Interface doesn't support scanning.
lo Interface doesn't support scanning.
##### module infos ######################
##### module parameters #################
##### /etc/modules ######################
##### modprobe options ##################
[/etc/modprobe.d/amd64-microcode-blacklist.conf]
blacklist microcode
[/etc/modprobe.d/blacklist-ath_pci.conf]
blacklist ath_pci
[/etc/modprobe.d/blacklist.conf]
blacklist evbug
blacklist usbmouse
blacklist usbkbd
blacklist eepro100
blacklist de4x5
blacklist eth1394
blacklist snd_intel8x0m
blacklist snd_aw2
blacklist i2c_i801
blacklist prism54
blacklist bcm43xx
blacklist garmin_gps
blacklist asus_acpi
blacklist snd_pcsp
blacklist pcspkr
blacklist amd76x_edac
[/etc/modprobe.d/blacklist-rare-network.conf]
alias net-pf-3 off
alias net-pf-6 off
alias net-pf-9 off
alias net-pf-11 off
alias net-pf-12 off
alias net-pf-19 off
alias net-pf-21 off
alias net-pf-36 off
[/etc/modprobe.d/intel-microcode-blacklist.conf]
blacklist microcode
[/etc/modprobe.d/iwlwifi.conf]
remove iwlwifi \
(/sbin/lsmod | grep -o -e ^iwlmvm -e ^iwldvm -e ^iwlwifi | xargs /sbin/rmmod) \
&& /sbin/modprobe -r mac80211
##### rc.local ##########################
grep: /etc/rc.local: No such file or directory
##### pm-utils ##########################
##### udev rules ########################
##### dmesg #############################
[ 71.883033] forcedeth 0000:00:0a.0 enp0s10: MSI enabled
[ 71.883843] IPv6: ADDRCONF(NETDEV_CHANGE): enp0s10: link becomes ready
[ 236.121550] nouveau 0000:03:00.0: Direct firmware load for nouveau/nvac_fuc084 failed with error -2
[ 236.121563] nouveau 0000:03:00.0: Direct firmware load for nouveau/nvac_fuc084d failed with error -2
[ 236.121565] nouveau 0000:03:00.0: msvld: unable to load firmware data
########## wireless info END ############
这是内部 Broadcom 无线网卡。
经过一整天的故障排除后，我决定清理电脑并安装 16.04，因为之前没有遇到任何问题。令人惊讶的是，这并没有解决问题。后来又升级回了 18.04。
答案1
如果某个设备以前一直正常工作，但突然停止工作，我喜欢测试硬件故障的可能性。如果我的鼠标或键盘不工作，我通常会尝试将其插入另一台计算机。如果我无法插入另一台计算机的硬件设备（如无线适配器）不工作，我会尝试使用 Ubuntu live USB 启动实时会话。我还会拍下启动消息屏幕的照片，并研究它，看看是否能找到任何关于可能存在硬件问题的有趣信息。如果 RAM 棒存在硬件问题，它几乎总会在计算机启动时打印在屏幕上。