我遇到了一个奇怪的问题，我的 Linux 机器只能在 5Ghz 频段连接到 WiFi 路由器，而在 2.4Ghz 上一切正常（但严重限制了互联网带宽）。我想这不是路由器的问题，因为我能够使用 5Ghz 频段全速连接我的 Galaxy Note 10。我怀疑这只是一个 Linux 配置问题。
我正在使用带有 5.8.0-41-generic 内核和 Broadcom BCM4360 802.11ac 无线网络适配器的 Ubuntu 20.10。
但让我们从头开始。我怀疑问题可能与切换到 Ubuntu 20.10 有关，但我不能 100% 确定。我发现韋斯特一些系统更新后设置被删除：
# iw reg get
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)
# iw reg set PL
# iw reg get
global
country PL: DFS-ETSI
(2400 - 2483 @ 40), (N/A, 20), (N/A)
(5150 - 5250 @ 80), (N/A, 23), (N/A), NO-OUTDOOR, AUTO-BW
(5250 - 5350 @ 80), (N/A, 20), (0 ms), NO-OUTDOOR, DFS, AUTO-BW
(5470 - 5725 @ 160), (N/A, 26), (0 ms), DFS
(5725 - 5875 @ 80), (N/A, 13), (N/A)
(57000 - 66000 @ 2160), (N/A, 40), (N/A)
我的 WiFi 路由器的当前设置是：
2.4Ghz
802.11 Mode: Mixed (802.11b, 802.11g and 802.11n)
Channel: Auto (Current Ch. 1)
Bandwidth: Auto
Power: 100
5Ghz
802.11 Mode: Mixed (802.11a and 802.11n/ac)
Channel: Auto (Current Ch. 100/80)
Bandwidth: Auto
Power: 100
我认为下面列出的东西可能会有帮助：
# iw list
Wiphy phy0
wiphy index: 0
max # scan SSIDs: 1
max scan IEs length: 0 bytes
max # sched scan SSIDs: 0
max # match sets: 0
max # scan plans: 1
max scan plan interval: -1
max scan plan iterations: 0
Retry short limit: 7
Retry long limit: 4
Coverage class: 0 (up to 0m)
Supported Ciphers:
* WEP40 (00-0f-ac:1)
* WEP104 (00-0f-ac:5)
* TKIP (00-0f-ac:2)
* CCMP-128 (00-0f-ac:4)
* CMAC (00-0f-ac:6)
Available Antennas: TX 0 RX 0
Supported interface modes:
* IBSS
* managed
Band 1:
Bitrates (non-HT):
* 1.0 Mbps
* 2.0 Mbps (short preamble supported)
* 5.5 Mbps (short preamble supported)
* 11.0 Mbps (short preamble supported)
* 6.0 Mbps
* 9.0 Mbps
* 12.0 Mbps
* 18.0 Mbps
* 24.0 Mbps
* 36.0 Mbps
* 48.0 Mbps
* 54.0 Mbps
Frequencies:
* 2412 MHz [1] (20.0 dBm)
* 2417 MHz [2] (20.0 dBm)
* 2422 MHz [3] (20.0 dBm)
* 2427 MHz [4] (20.0 dBm)
* 2432 MHz [5] (20.0 dBm)
* 2437 MHz [6] (20.0 dBm)
* 2442 MHz [7] (20.0 dBm)
* 2447 MHz [8] (20.0 dBm)
* 2452 MHz [9] (20.0 dBm)
* 2457 MHz [10] (20.0 dBm)
* 2462 MHz [11] (20.0 dBm)
* 2467 MHz [12] (20.0 dBm)
* 2472 MHz [13] (20.0 dBm)
* 2484 MHz [14] (disabled)
Band 2:
Bitrates (non-HT):
* 6.0 Mbps
* 9.0 Mbps
* 12.0 Mbps
* 18.0 Mbps
* 24.0 Mbps
* 36.0 Mbps
* 48.0 Mbps
* 54.0 Mbps
Frequencies:
* 5160 MHz [32] (23.0 dBm)
* 5170 MHz [34] (23.0 dBm)
* 5180 MHz [36] (23.0 dBm)
* 5190 MHz [38] (23.0 dBm)
* 5200 MHz [40] (23.0 dBm)
* 5210 MHz [42] (23.0 dBm)
* 5220 MHz [44] (23.0 dBm)
* 5230 MHz [46] (23.0 dBm)
* 5240 MHz [48] (23.0 dBm)
* 5250 MHz [50] (disabled)
* 5260 MHz [52] (20.0 dBm) (radar detection)
* 5270 MHz [54] (20.0 dBm) (radar detection)
* 5280 MHz [56] (20.0 dBm) (radar detection)
* 5290 MHz [58] (20.0 dBm) (radar detection)
* 5300 MHz [60] (20.0 dBm) (radar detection)
* 5310 MHz [62] (20.0 dBm) (radar detection)
* 5320 MHz [64] (20.0 dBm) (radar detection)
* 5330 MHz [66] (20.0 dBm) (radar detection)
* 5340 MHz [68] (20.0 dBm) (radar detection)
* 5350 MHz [70] (disabled)
* 5360 MHz [72] (disabled)
* 5370 MHz [74] (disabled)
* 5380 MHz [76] (disabled)
* 5390 MHz [78] (disabled)
* 5400 MHz [80] (disabled)
* 5410 MHz [82] (disabled)
* 5420 MHz [84] (disabled)
* 5430 MHz [86] (disabled)
* 5440 MHz [88] (disabled)
* 5450 MHz [90] (disabled)
* 5460 MHz [92] (disabled)
* 5470 MHz [94] (disabled)
* 5480 MHz [96] (26.0 dBm) (radar detection)
* 5490 MHz [98] (26.0 dBm) (radar detection)
* 5500 MHz [100] (26.0 dBm) (radar detection)
* 5510 MHz [102] (26.0 dBm) (radar detection)
* 5520 MHz [104] (26.0 dBm) (radar detection)
* 5530 MHz [106] (26.0 dBm) (radar detection)
* 5540 MHz [108] (26.0 dBm) (radar detection)
* 5550 MHz [110] (26.0 dBm) (radar detection)
* 5560 MHz [112] (26.0 dBm) (radar detection)
* 5570 MHz [114] (26.0 dBm) (radar detection)
* 5580 MHz [116] (26.0 dBm) (radar detection)
* 5590 MHz [118] (26.0 dBm) (radar detection)
* 5600 MHz [120] (26.0 dBm) (radar detection)
* 5610 MHz [122] (26.0 dBm) (radar detection)
* 5620 MHz [124] (26.0 dBm) (radar detection)
* 5630 MHz [126] (26.0 dBm) (radar detection)
* 5640 MHz [128] (26.0 dBm) (radar detection)
* 5650 MHz [130] (26.0 dBm) (radar detection)
* 5660 MHz [132] (26.0 dBm) (radar detection)
* 5670 MHz [134] (26.0 dBm) (radar detection)
* 5680 MHz [136] (26.0 dBm) (radar detection)
* 5690 MHz [138] (26.0 dBm) (radar detection)
* 5700 MHz [140] (26.0 dBm) (radar detection)
* 5710 MHz [142] (26.0 dBm) (radar detection)
* 5720 MHz [144] (disabled)
* 5725 MHz [145] (disabled)
* 5730 MHz [146] (disabled)
* 5735 MHz [147] (13.0 dBm)
* 5740 MHz [148] (13.0 dBm)
* 5745 MHz [149] (13.0 dBm)
* 5750 MHz [150] (13.0 dBm)
* 5755 MHz [151] (13.0 dBm)
* 5760 MHz [152] (13.0 dBm)
* 5765 MHz [153] (13.0 dBm)
* 5770 MHz [154] (13.0 dBm)
* 5775 MHz [155] (13.0 dBm)
* 5780 MHz [156] (13.0 dBm)
* 5785 MHz [157] (13.0 dBm)
* 5790 MHz [158] (13.0 dBm)
* 5795 MHz [159] (13.0 dBm)
* 5800 MHz [160] (13.0 dBm)
* 5805 MHz [161] (13.0 dBm)
* 5810 MHz [162] (13.0 dBm)
* 5815 MHz [163] (13.0 dBm)
* 5820 MHz [164] (13.0 dBm)
* 5825 MHz [165] (13.0 dBm)
* 5830 MHz [166] (13.0 dBm)
* 5840 MHz [168] (13.0 dBm)
* 5850 MHz [170] (13.0 dBm)
* 5860 MHz [172] (13.0 dBm)
* 5870 MHz [174] (disabled)
* 5880 MHz [176] (disabled)
* 5890 MHz [178] (disabled)
* 5900 MHz [180] (disabled)
* 5910 MHz [182] (disabled)
* 5920 MHz [184] (disabled)
* 5930 MHz [186] (disabled)
* 5940 MHz [188] (disabled)
* 5950 MHz [0] (disabled)
* 5960 MHz [2] (disabled)
* 5970 MHz [4] (disabled)
* 5980 MHz [6] (disabled)
* 5990 MHz [8] (disabled)
* 6000 MHz [10] (disabled)
* 6010 MHz [12] (disabled)
* 6020 MHz [14] (disabled)
* 6030 MHz [16] (disabled)
* 6040 MHz [18] (disabled)
* 6050 MHz [20] (disabled)
* 6060 MHz [22] (disabled)
* 6070 MHz [24] (disabled)
* 6080 MHz [26] (disabled)
* 6090 MHz [28] (disabled)
* 6100 MHz [30] (disabled)
* 6110 MHz [32] (disabled)
* 6120 MHz [34] (disabled)
* 6130 MHz [36] (disabled)
* 6140 MHz [38] (disabled)
Supported commands:
* set_interface
* new_key
* join_ibss
* set_pmksa
* del_pmksa
* flush_pmksa
* connect
* disconnect
WoWLAN support:
* wake up on disconnect
* wake up on magic packet
* can do GTK rekeying
* wake up on GTK rekey failure
* wake up on EAP identity request
software interface modes (can always be added):
interface combinations are not supported
Device supports scan flush.
Supported extended features:
我将非常感激任何有关正在发生什么以及如何利用 5Ghz 频段的线索。