我买了一台新笔记本电脑 Acer TravelMate P-645-MG，内置 3G 卡。
我可以看到调制解调器dmesg
[ 5.550759] usb 2-5: new high-speed USB device number 6 using xhci_hcd
[ 5.569075] usb 2-5: New USB device found, idVendor=12d1, idProduct=1570
[ 5.569076] usb 2-5: New USB device strings: Mfr=5, Product=4, SerialNumber=0
[ 5.569078] usb 2-5: Product: HUAWEI Mobile Broadband Module
[ 5.569079] usb 2-5: Manufacturer: Huawei Technologies Co., Ltd.
[ 6.434521] usb 2-5: GSM modem (1-port) converter now attached to ttyUSB0
[ 6.442747] usb 2-5: GSM modem (1-port) converter now attached to ttyUSB1
[ 6.443201] usb 2-5: GSM modem (1-port) converter now attached to ttyUSB2
[ 7.589287] usb 2-5: USB disconnect, device number 6
断开的线路看上去非常可疑。
但它没有出现在lsusb
$ lsusb
Bus 001 Device 002: ID 8087:8000 Intel Corp.
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 002 Device 005: ID 1c7a:0603 LighTuning Technology Inc.
Bus 002 Device 004: ID 8087:07dc Intel Corp.
Bus 002 Device 003: ID 1bcf:2c57 Sunplus Innovation Technology Inc.
Bus 002 Device 032: ID 046d:c52b Logitech, Inc. Unifying Receiver
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
因此我在 NetworkManager 中看不到它