我有一台运行 Ubuntu 20.04 的戴尔笔记本电脑。wifi 无法连接到 2.4Ghz 频段路由器（但可以连接到 5Ghz）。
nm-connection-editor在谷歌上搜索了这个问题后，我尝试按照建议手动将频段设置为 2.4Ghz这里. 这并没有帮助。
网络设置已保存，您可以从这里看到：
sudo cat /etc/NetworkManager/system-connections/name.nmconnection
[connection]
id=name
uuid=*******
type=wifi
autoconnect-priority=1
interface-name=wlp2s0
permissions=
[wifi]
band=bg
mac-address-blacklist=
mode=infrastructure
ssid=name
[wifi-security]
key-mgmt=wpa-psk
psk=*******
[ipv4]
dns-search=
method=auto
[ipv6]
addr-gen-mode=stable-privacy
dns-search=
ip6-privacy=0
method=auto
[proxy]
我还尝试通过重新启动笔记本电脑来重新启动网络管理器sudo service network-manager restart。
您对如何解决该问题有什么建议吗？任何帮助都将不胜感激。
我提供了一些有关我的系统的附加信息：
sudo lshw -C network -sanitize
*-network
description: Wireless interface
product: BCM43602 802.11ac Wireless LAN SoC
vendor: Broadcom Inc. and subsidiaries
physical id: 0
bus info: pci@0000:02:00.0
logical name: wlp2s0
version: 01
serial: [REMOVED]
width: 64 bits
clock: 33MHz
capabilities: pm msi pciexpress bus_master cap_list ethernet physical wireless
configuration: broadcast=yes driver=brcmfmac driverversion=7.35.177.61 firmware=01-ea662a8c ip=[REMOVED] latency=0 multicast=yes wireless=IEEE 802.11
resources: irq:143 memory:dd800000-dd807fff memory:dd400000-dd7fffff
lspci -vnn | grep -i net -A8
02:00.0 Network controller [0280]: Broadcom Inc. and subsidiaries BCM43602 802.11ac Wireless LAN SoC [14e4:43ba] (rev 01)
Subsystem: Dell BCM43602 802.11ac Wireless LAN SoC [1028:0020]
Flags: bus master, fast devsel, latency 0, IRQ 143
Memory at dd800000 (64-bit, non-prefetchable) [size=32K]
Memory at dd400000 (64-bit, non-prefetchable) [size=4M]
Capabilities: <access denied>
Kernel driver in use: brcmfmac
Kernel modules: brcmfmac
sudo dmesg | grep brcm
[ 12.679132] usbcore: registered new interface driver brcmfmac
[ 12.679176] brcmfmac 0000:02:00.0: enabling device (0000 -> 0002)
[ 12.784576] brcmfmac: brcmf_fw_alloc_request: using brcm/brcmfmac43602-pcie for chip BCM43602/1
[ 12.787581] brcmfmac 0000:02:00.0: Direct firmware load for brcm/brcmfmac43602-pcie.Dell Inc.-XPS 15 9550.txt failed with error -2
[ 12.787600] brcmfmac 0000:02:00.0: Direct firmware load for brcm/brcmfmac43602-pcie.txt failed with error -2
[ 12.828507] bluetooth hci0: Direct firmware load for brcm/BCM20703A1-0a5c-6410.hcd failed with error -2
[ 12.828509] Bluetooth: hci0: BCM: Patch brcm/BCM20703A1-0a5c-6410.hcd not found
[ 13.322327] brcmfmac: brcmf_fw_alloc_request: using brcm/brcmfmac43602-pcie for chip BCM43602/1
[ 13.322366] brcmfmac: brcmf_c_process_clm_blob: no clm_blob available (err=-2), device may have limited channels available
[ 13.322852] brcmfmac: brcmf_c_preinit_dcmds: Firmware: BCM43602/1 wl0: Nov 10 2015 06:38:10 version 7.35.177.61 (r598657) FWID 01-ea662a8c
[ 13.374104] brcmfmac 0000:02:00.0 wlp2s0: renamed from wlan0
[ 23.092812] ieee80211 phy0: brcmf_inetaddr_changed: fail to get arp ip table err:-52
[ 41.710983] ieee80211 phy0: brcmf_inetaddr_changed: fail to get arp ip table err:-52
[ 75.081959] ieee80211 phy0: brcmf_inetaddr_changed: fail to get arp ip table err:-52
[ 167.625935] ieee80211 phy0: brcmf_inetaddr_changed: fail to get arp ip table err:-52
[ 178.201563] ieee80211 phy0: brcmf_inetaddr_changed: fail to get arp ip table err:-52
[ 219.046639] ieee80211 phy0: brcmf_inetaddr_changed: fail to get arp ip table err:-52
[ 378.890113] ieee80211 phy0: brcmf_inetaddr_changed: fail to get arp ip table err:-52
[ 395.718585] ieee80211 phy0: brcmf_inetaddr_changed: fail to get arp ip table err:-52
[ 429.483904] ieee80211 phy0: brcmf_inetaddr_changed: fail to get arp ip table err:-52
我读这里可以将其添加options iwlwifi 11n_disable=1到 /etc/modprobe.d/iwlwifi.conf 文件中。我不确定这是否适合在我的系统上执行。iwlwifi 是否特定于英特尔？
这是我当前的文件：
cat /etc/modprobe.d/iwlwifi.conf
# /etc/modprobe.d/iwlwifi.conf
# iwlwifi will dyamically load either iwldvm or iwlmvm depending on the
# microcode file installed on the system. When removing iwlwifi, first
# remove the iwl?vm module and then iwlwifi.
remove iwlwifi \
(/sbin/lsmod | grep -o -e ^iwlmvm -e ^iwldvm -e ^iwlwifi | xargs /sbin/rmmod) \
&& /sbin/modprobe -r mac80211
根据 Raffles 的要求，我还添加了 iwlist chan 的输出：
iwlist chan
lo no frequency information.
wlp2s0 32 channels in total; available frequencies :
Channel 01 : 2.412 GHz
Channel 02 : 2.417 GHz
Channel 03 : 2.422 GHz
Channel 04 : 2.427 GHz
Channel 05 : 2.432 GHz
Channel 06 : 2.437 GHz
Channel 07 : 2.442 GHz
Channel 08 : 2.447 GHz
Channel 09 : 2.452 GHz
Channel 10 : 2.457 GHz
Channel 11 : 2.462 GHz
Channel 12 : 2.467 GHz
Channel 13 : 2.472 GHz
Channel 34 : 5.17 GHz
Channel 36 : 5.18 GHz
Channel 38 : 5.19 GHz
Channel 40 : 5.2 GHz
Channel 42 : 5.21 GHz
Channel 44 : 5.22 GHz
Channel 46 : 5.23 GHz
Channel 48 : 5.24 GHz
Channel 52 : 5.26 GHz
Channel 56 : 5.28 GHz
Channel 60 : 5.3 GHz
Channel 64 : 5.32 GHz
Channel 100 : 5.5 GHz
Channel 104 : 5.52 GHz
Channel 108 : 5.54 GHz
Channel 112 : 5.56 GHz
Channel 116 : 5.58 GHz
Channel 120 : 5.6 GHz
Channel 124 : 5.62 GHz
Current Frequency:5.24 GHz (Channel 48)
docker0 no frequency information.
答案1
如果你有条件，我建议你投资一个Wifi 网状系统它比旧系统更安全，应该可以解决您的问题。请确保您选择的系统可以支持 VPN，因为有些系统不支持（例如我的是 Velop，我很后悔）。让整个家庭网络通过您最喜欢的 VPN 比单个机器更有利。通过路由器进行 VPN
答案2
就我而言，我运行了 nm-connection-editor 命令并编辑了我的 2.4GHz 网络。在此工具中，您可以强制使用 B/G（2.4GHz）频段。这解决了我在 Ubuntu 22.04 上的问题。无线 7265。