我在 Ubuntu 17.04 下使用华为 E3372 LTE 调制解调器。
/eth/network/interfaces
allow-hotplug wwx001e101f0000
iface wwx001e101f0000 inet dhcp
pre-up /bin/echo -e "AT^NDISDUP=1,1,\"internet\"\r" > /dev/ttyUSB0
post-down /bin/echo -ne 'AT^NDISDUP=1,0\r\n' > /dev/ttyUSB
它的工作原理是：
- 我把 USB 插上，然后重启
- 我第一次插入机器
此案例的日志：
Jul 24 22:50:06 ubuntu-linux kernel: [ 143.152401] random: crng init done
Jul 24 22:50:08 ubuntu-linux kernel: [ 145.092450] usb 1-2: new high-speed USB device number 3 using ehci-pci
Jul 24 22:50:08 ubuntu-linux kernel: [ 145.240887] usb 1-2: New USB device found, idVendor=12d1, idProduct=14fe
Jul 24 22:50:08 ubuntu-linux kernel: [ 145.240890] usb 1-2: New USB device strings: Mfr=1, Product=2, SerialNumber=3
Jul 24 22:50:08 ubuntu-linux kernel: [ 145.240891] usb 1-2: Product: HUAWEI_MOBILE
Jul 24 22:50:08 ubuntu-linux kernel: [ 145.240892] usb 1-2: Manufacturer: HUAWEI_MOBILE
Jul 24 22:50:08 ubuntu-linux kernel: [ 145.240893] usb 1-2: SerialNumber: 0123456789ABCDEF
Jul 24 22:50:08 ubuntu-linux systemd[1]: Created slice system-usb_modeswitch.slice.
Jul 24 22:50:08 ubuntu-linux systemd[1]: Starting USB_ModeSwitch_1-2:1.0...
Jul 24 22:50:08 ubuntu-linux usb_modeswitch_dispatcher[1405]: Could not read attribute: No such file or directory
Jul 24 22:50:08 ubuntu-linux kernel: [ 145.432751] usb-storage 1-2:1.0: USB Mass Storage device detected
Jul 24 22:50:08 ubuntu-linux kernel: [ 145.432874] scsi host8: usb-storage 1-2:1.0
Jul 24 22:50:08 ubuntu-linux kernel: [ 145.433024] usbcore: registered new interface driver usb-storage
Jul 24 22:50:08 ubuntu-linux kernel: [ 145.438274] usbcore: registered new interface driver uas
Jul 24 22:50:09 ubuntu-linux kernel: [ 146.461913] scsi 8:0:0:0: CD-ROM HUAWEI Mass Storage 2.31 PQ: 0 ANSI: 2
Jul 24 22:50:09 ubuntu-linux kernel: [ 146.466068] scsi 8:0:0:1: Direct-Access HUAWEI TF CARD Storage 2.31 PQ: 0 ANSI: 2
Jul 24 22:50:08 ubuntu-linux usb_modeswitch_dispatcher[1405]: message repeated 2 times: [ Could not read attribute: No such file or directory]
Jul 24 22:50:09 ubuntu-linux usb_modeswitch: switch device 12d1:14fe on 001/003
Jul 24 22:50:09 ubuntu-linux kernel: [ 146.512229] sr 8:0:0:0: [sr1] scsi-1 drive
Jul 24 22:50:09 ubuntu-linux kernel: [ 146.512465] sr 8:0:0:0: Attached scsi CD-ROM sr1
Jul 24 22:50:09 ubuntu-linux kernel: [ 146.512562] sr 8:0:0:0: Attached scsi generic sg2 type 5
Jul 24 22:50:09 ubuntu-linux kernel: [ 146.512784] sd 8:0:0:1: Attached scsi generic sg3 type 0
Jul 24 22:50:09 ubuntu-linux kernel: [ 146.550305] sd 8:0:0:1: [sdb] Attached SCSI removable disk
Jul 24 22:50:09 ubuntu-linux systemd-udevd[1435]: Process '/lib/udev/hdparm' failed with exit code 2.
Jul 24 22:50:09 ubuntu-linux systemd-udevd[1435]: inotify_add_watch(9, /dev/sdb, 10) failed: No such file or directory
Jul 24 22:50:09 ubuntu-linux systemd-udevd[1429]: inotify_add_watch(9, /dev/sdb, 10) failed: No such file or directory
Jul 24 22:50:09 ubuntu-linux kernel: [ 146.786589] usb 1-2: USB disconnect, device number 3
Jul 24 22:50:11 ubuntu-linux kernel: [ 147.896712] usb 1-2: new high-speed USB device number 4 using ehci-pci
Jul 24 22:50:11 ubuntu-linux kernel: [ 148.045492] usb 1-2: New USB device found, idVendor=12d1, idProduct=1506
Jul 24 22:50:11 ubuntu-linux kernel: [ 148.045495] usb 1-2: New USB device strings: Mfr=1, Product=2, SerialNumber=0
Jul 24 22:50:11 ubuntu-linux kernel: [ 148.045497] usb 1-2: Product: HUAWEI_MOBILE
Jul 24 22:50:11 ubuntu-linux kernel: [ 148.045498] usb 1-2: Manufacturer: HUAWEI_MOBILE
Jul 24 22:50:11 ubuntu-linux kernel: [ 148.684183] usb-storage 1-2:1.3: USB Mass Storage device detected
Jul 24 22:50:11 ubuntu-linux kernel: [ 148.684397] scsi host8: usb-storage 1-2:1.3
Jul 24 22:50:11 ubuntu-linux kernel: [ 148.685635] usb-storage 1-2:1.4: USB Mass Storage device detected
Jul 24 22:50:11 ubuntu-linux kernel: [ 148.685737] scsi host9: usb-storage 1-2:1.4
Jul 24 22:50:11 ubuntu-linux kernel: [ 148.703822] usbcore: registered new interface driver usbserial
Jul 24 22:50:11 ubuntu-linux kernel: [ 148.703834] usbcore: registered new interface driver usbserial_generic
Jul 24 22:50:11 ubuntu-linux kernel: [ 148.703845] usbserial: USB Serial support registered for generic
Jul 24 22:50:11 ubuntu-linux kernel: [ 148.714421] usbcore: registered new interface driver option
Jul 24 22:50:11 ubuntu-linux kernel: [ 148.714437] usbserial: USB Serial support registered for GSM modem (1-port)
Jul 24 22:50:11 ubuntu-linux kernel: [ 148.714507] option 1-2:1.0: GSM modem (1-port) converter detected
Jul 24 22:50:11 ubuntu-linux kernel: [ 148.716110] usb 1-2: GSM modem (1-port) converter now attached to ttyUSB0
Jul 24 22:50:11 ubuntu-linux kernel: [ 148.716137] option 1-2:1.1: GSM modem (1-port) converter detected
Jul 24 22:50:11 ubuntu-linux kernel: [ 148.716270] usb 1-2: GSM modem (1-port) converter now attached to ttyUSB1
Jul 24 22:50:11 ubuntu-linux kernel: [ 148.717436] usbcore: registered new interface driver cdc_ncm
Jul 24 22:50:11 ubuntu-linux kernel: [ 148.720558] usbcore: registered new interface driver cdc_wdm
Jul 24 22:50:11 ubuntu-linux kernel: [ 148.819152] huawei_cdc_ncm 1-2:1.2: MAC-Address: 00:1e:10:1f:00:00
Jul 24 22:50:11 ubuntu-linux kernel: [ 148.819156] huawei_cdc_ncm 1-2:1.2: setting rx_max = 16384
Jul 24 22:50:11 ubuntu-linux kernel: [ 148.827157] huawei_cdc_ncm 1-2:1.2: NDP will be placed at end of frame for this device.
Jul 24 22:50:11 ubuntu-linux kernel: [ 148.827378] huawei_cdc_ncm 1-2:1.2: cdc-wdm0: USB WDM device
Jul 24 22:50:11 ubuntu-linux kernel: [ 148.827611] huawei_cdc_ncm 1-2:1.2 wwan0: register 'huawei_cdc_ncm' at usb-0000:00:1d.7-2, Huawei CDC NCM device, 00:1e:10:1f:00:00
Jul 24 22:50:11 ubuntu-linux kernel: [ 148.827675] usbcore: registered new interface driver huawei_cdc_ncm
Jul 24 22:50:11 ubuntu-linux usb_modeswitch[1405]: usb_modeswitch: switched to 12d1:1506 on 1/4
Jul 24 22:50:11 ubuntu-linux usb_modeswitch_dispatcher[1405]: Could not read attribute: No such file or directory
Jul 24 22:50:11 ubuntu-linux kernel: [ 148.831382] huawei_cdc_ncm 1-2:1.2 wwx001e101f0000: renamed from wwan0
Jul 24 22:50:12 ubuntu-linux systemd[1]: Found device Modem/Networkcard.
Jul 24 22:50:12 ubuntu-linux systemd[1]: Started ifup for wwx001e101f0000.
Jul 24 22:50:12 ubuntu-linux dhclient[1518]: Internet Systems Consortium DHCP Client 4.3.5
Jul 24 22:50:12 ubuntu-linux sh[1500]: Internet Systems Consortium DHCP Client 4.3.5
Jul 24 22:50:12 ubuntu-linux sh[1500]: Copyright 2004-2016 Internet Systems Consortium.
Jul 24 22:50:12 ubuntu-linux sh[1500]: All rights reserved.
Jul 24 22:50:12 ubuntu-linux sh[1500]: For info, please visit https://www.isc.org/software/dhcp/
Jul 24 22:50:12 ubuntu-linux dhclient[1518]: Copyright 2004-2016 Internet Systems Consortium.
Jul 24 22:50:12 ubuntu-linux dhclient[1518]: All rights reserved.
Jul 24 22:50:12 ubuntu-linux dhclient[1518]: For info, please visit https://www.isc.org/software/dhcp/
Jul 24 22:50:12 ubuntu-linux dhclient[1518]:
Jul 24 22:50:12 ubuntu-linux dhclient[1518]: Listening on LPF/wwx001e101f0000/00:1e:10:1f:00:00
Jul 24 22:50:12 ubuntu-linux sh[1500]: Listening on LPF/wwx001e101f0000/00:1e:10:1f:00:00
Jul 24 22:50:12 ubuntu-linux sh[1500]: Sending on LPF/wwx001e101f0000/00:1e:10:1f:00:00
Jul 24 22:50:12 ubuntu-linux sh[1500]: Sending on Socket/fallback
Jul 24 22:50:12 ubuntu-linux sh[1500]: DHCPREQUEST of 100.64.119.246 on wwx001e101f0000 to 255.255.255.255 port 67 (xid=0x4a727742)
Jul 24 22:50:12 ubuntu-linux dhclient[1518]: Sending on LPF/wwx001e101f0000/00:1e:10:1f:00:00
Jul 24 22:50:12 ubuntu-linux dhclient[1518]: Sending on Socket/fallback
Jul 24 22:50:12 ubuntu-linux dhclient[1518]: DHCPREQUEST of 100.64.119.246 on wwx001e101f0000 to 255.255.255.255 port 67 (xid=0x4a727742)
Jul 24 22:50:12 ubuntu-linux kernel: [ 149.720148] scsi 9:0:0:0: Direct-Access HUAWEI TF CARD Storage 2.31 PQ: 0 ANSI: 2
Jul 24 22:50:12 ubuntu-linux kernel: [ 149.720637] scsi 8:0:0:0: CD-ROM HUAWEI Mass Storage 2.31 PQ: 0 ANSI: 2
Jul 24 22:50:12 ubuntu-linux kernel: [ 149.720967] sd 9:0:0:0: Attached scsi generic sg2 type 0
Jul 24 22:50:12 ubuntu-linux kernel: [ 149.729707] sr 8:0:0:0: [sr1] scsi-1 drive
Jul 24 22:50:12 ubuntu-linux kernel: [ 149.729828] sr 8:0:0:0: Attached scsi CD-ROM sr1
Jul 24 22:50:12 ubuntu-linux kernel: [ 149.729885] sr 8:0:0:0: Attached scsi generic sg3 type 5
Jul 24 22:50:12 ubuntu-linux kernel: [ 149.731040] sd 9:0:0:0: [sdb] Attached SCSI removable disk
Jul 24 22:50:12 ubuntu-linux kernel: [ 149.773904] sr 8:0:0:0: [sr1] tag#0 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE
Jul 24 22:50:12 ubuntu-linux kernel: [ 149.773907] sr 8:0:0:0: [sr1] tag#0 Sense Key : Medium Error [current]
Jul 24 22:50:12 ubuntu-linux kernel: [ 149.773911] sr 8:0:0:0: [sr1] tag#0 Add. Sense: Unrecovered read error
Jul 24 22:50:12 ubuntu-linux kernel: [ 149.773913] sr 8:0:0:0: [sr1] tag#0 CDB: Read(10) 28 00 00 00 8d fc 00 00 02 00
Jul 24 22:50:12 ubuntu-linux kernel: [ 149.773915] blk_update_request: critical medium error, dev sr1, sector 145392
Jul 24 22:50:12 ubuntu-linux kernel: [ 149.781680] sr 8:0:0:0: [sr1] tag#0 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE
Jul 24 22:50:12 ubuntu-linux kernel: [ 149.781682] sr 8:0:0:0: [sr1] tag#0 Sense Key : Medium Error [current]
Jul 24 22:50:12 ubuntu-linux kernel: [ 149.781683] sr 8:0:0:0: [sr1] tag#0 Add. Sense: Unrecovered read error
Jul 24 22:50:12 ubuntu-linux kernel: [ 149.781685] sr 8:0:0:0: [sr1] tag#0 CDB: Read(10) 28 00 00 00 8d fc 00 00 02 00
Jul 24 22:50:12 ubuntu-linux kernel: [ 149.781686] blk_update_request: critical medium error, dev sr1, sector 145392
Jul 24 22:50:12 ubuntu-linux kernel: [ 149.781727] Buffer I/O error on dev sr1, logical block 18174, async page read
Jul 24 22:50:12 ubuntu-linux usb_modeswitch_dispatcher[1405]: Unable to open bind list file: No such file or directory
Jul 24 22:50:12 ubuntu-linux usb_modeswitch[1405]: usb_modeswitch: add device ID 12d1:1506 to driver option
Jul 24 22:50:12 ubuntu-linux usb_modeswitch[1405]: usb_modeswitch: please report the device ID to the Linux USB developers!
Jul 24 22:50:13 ubuntu-linux kernel: [ 149.932570] sr 8:0:0:0: [sr1] tag#0 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE
Jul 24 22:50:13 ubuntu-linux kernel: [ 149.932574] sr 8:0:0:0: [sr1] tag#0 Sense Key : Medium Error [current]
Jul 24 22:50:13 ubuntu-linux kernel: [ 149.932576] sr 8:0:0:0: [sr1] tag#0 Add. Sense: Unrecovered read error
Jul 24 22:50:13 ubuntu-linux kernel: [ 149.932578] sr 8:0:0:0: [sr1] tag#0 CDB: Read(10) 28 00 00 00 8c 80 00 00 3c 00
Jul 24 22:50:13 ubuntu-linux kernel: [ 149.932580] blk_update_request: critical medium error, dev sr1, sector 143872
Jul 24 22:50:13 ubuntu-linux kernel: [ 149.942133] sr 8:0:0:0: [sr1] tag#0 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE
Jul 24 22:50:13 ubuntu-linux kernel: [ 149.942136] sr 8:0:0:0: [sr1] tag#0 Sense Key : Medium Error [current]
Jul 24 22:50:13 ubuntu-linux kernel: [ 149.942138] sr 8:0:0:0: [sr1] tag#0 Add. Sense: Unrecovered read error
Jul 24 22:50:13 ubuntu-linux kernel: [ 149.942140] sr 8:0:0:0: [sr1] tag#0 CDB: Read(10) 28 00 00 00 8c 80 00 00 02 00
Jul 24 22:50:13 ubuntu-linux kernel: [ 149.942142] blk_update_request: critical medium error, dev sr1, sector 143872
Jul 24 22:50:13 ubuntu-linux kernel: [ 149.942184] Buffer I/O error on dev sr1, logical block 17984, async page read
Jul 24 22:50:13 ubuntu-linux kernel: [ 149.975782] sr 8:0:0:0: [sr1] tag#0 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE
Jul 24 22:50:13 ubuntu-linux kernel: [ 149.975786] sr 8:0:0:0: [sr1] tag#0 Sense Key : Medium Error [current]
Jul 24 22:50:13 ubuntu-linux kernel: [ 149.975787] sr 8:0:0:0: [sr1] tag#0 Add. Sense: Unrecovered read error
Jul 24 22:50:13 ubuntu-linux kernel: [ 149.975790] sr 8:0:0:0: [sr1] tag#0 CDB: Read(10) 28 00 00 00 8d fa 00 00 02 00
Jul 24 22:50:13 ubuntu-linux kernel: [ 149.975792] blk_update_request: critical medium error, dev sr1, sector 145384
Jul 24 22:50:13 ubuntu-linux kernel: [ 149.985490] sr 8:0:0:0: [sr1] tag#0 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE
Jul 24 22:50:13 ubuntu-linux kernel: [ 149.985493] sr 8:0:0:0: [sr1] tag#0 Sense Key : Medium Error [current]
Jul 24 22:50:13 ubuntu-linux kernel: [ 149.985495] sr 8:0:0:0: [sr1] tag#0 Add. Sense: Unrecovered read error
Jul 24 22:50:13 ubuntu-linux kernel: [ 149.985498] sr 8:0:0:0: [sr1] tag#0 CDB: Read(10) 28 00 00 00 8d fa 00 00 02 00
Jul 24 22:50:13 ubuntu-linux kernel: [ 149.985500] blk_update_request: critical medium error, dev sr1, sector 145384
Jul 24 22:50:13 ubuntu-linux kernel: [ 149.985576] Buffer I/O error on dev sr1, logical block 18173, async page read
Jul 24 22:50:13 ubuntu-linux kernel: [ 150.062111] sr 8:0:0:0: [sr1] tag#0 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE
Jul 24 22:50:13 ubuntu-linux kernel: [ 150.062114] sr 8:0:0:0: [sr1] tag#0 Sense Key : Medium Error [current]
Jul 24 22:50:13 ubuntu-linux kernel: [ 150.062116] sr 8:0:0:0: [sr1] tag#0 Add. Sense: Unrecovered read error
Jul 24 22:50:13 ubuntu-linux kernel: [ 150.062117] sr 8:0:0:0: [sr1] tag#0 CDB: Read(10) 28 00 00 00 8d f6 00 00 02 00
Jul 24 22:50:13 ubuntu-linux kernel: [ 150.062119] blk_update_request: critical medium error, dev sr1, sector 145368
Jul 24 22:50:13 ubuntu-linux kernel: [ 150.069790] sr 8:0:0:0: [sr1] tag#0 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE
Jul 24 22:50:13 ubuntu-linux kernel: [ 150.069796] sr 8:0:0:0: [sr1] tag#0 Sense Key : Medium Error [current]
Jul 24 22:50:13 ubuntu-linux kernel: [ 150.069797] sr 8:0:0:0: [sr1] tag#0 Add. Sense: Unrecovered read error
Jul 24 22:50:13 ubuntu-linux kernel: [ 150.069799] sr 8:0:0:0: [sr1] tag#0 CDB: Read(10) 28 00 00 00 8d f6 00 00 02 00
Jul 24 22:50:13 ubuntu-linux kernel: [ 150.069801] blk_update_request: critical medium error, dev sr1, sector 145368
Jul 24 22:50:13 ubuntu-linux kernel: [ 150.069842] Buffer I/O error on dev sr1, logical block 18171, async page read
Jul 24 22:50:13 ubuntu-linux kernel: [ 150.102667] sr 8:0:0:0: [sr1] tag#0 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE
Jul 24 22:50:13 ubuntu-linux kernel: [ 150.102669] sr 8:0:0:0: [sr1] tag#0 Sense Key : Medium Error [current]
Jul 24 22:50:13 ubuntu-linux kernel: [ 150.102671] sr 8:0:0:0: [sr1] tag#0 Add. Sense: Unrecovered read error
Jul 24 22:50:13 ubuntu-linux kernel: [ 150.102673] sr 8:0:0:0: [sr1] tag#0 CDB: Read(10) 28 00 00 00 8c 80 00 00 3c 00
Jul 24 22:50:13 ubuntu-linux kernel: [ 150.102674] blk_update_request: critical medium error, dev sr1, sector 143872
Jul 24 22:50:13 ubuntu-linux kernel: [ 150.110487] sr 8:0:0:0: [sr1] tag#0 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE
Jul 24 22:50:13 ubuntu-linux kernel: [ 150.110489] sr 8:0:0:0: [sr1] tag#0 Sense Key : Medium Error [current]
Jul 24 22:50:13 ubuntu-linux kernel: [ 150.110490] sr 8:0:0:0: [sr1] tag#0 Add. Sense: Unrecovered read error
Jul 24 22:50:13 ubuntu-linux kernel: [ 150.110492] sr 8:0:0:0: [sr1] tag#0 CDB: Read(10) 28 00 00 00 8c 80 00 00 02 00
Jul 24 22:50:13 ubuntu-linux kernel: [ 150.110494] blk_update_request: critical medium error, dev sr1, sector 143872
Jul 24 22:50:13 ubuntu-linux kernel: [ 150.110537] Buffer I/O error on dev sr1, logical block 17984, async page read
Jul 24 22:50:13 ubuntu-linux kernel: [ 150.127395] Buffer I/O error on dev sr1, logical block 18170, async page read
Jul 24 22:50:15 ubuntu-linux dhclient[1518]: DHCPREQUEST of 100.64.119.246 on wwx001e101f0000 to 255.255.255.255 port 67 (xid=0x4a727742)
Jul 24 22:50:15 ubuntu-linux sh[1500]: DHCPREQUEST of 100.64.119.246 on wwx001e101f0000 to 255.255.255.255 port 67 (xid=0x4a727742)
Jul 24 22:50:15 ubuntu-linux dhclient[1518]: DHCPNAK from 100.64.25.233 (xid=0x4277724a)
Jul 24 22:50:15 ubuntu-linux sh[1500]: DHCPNAK from 100.64.25.233 (xid=0x4277724a)
Jul 24 22:50:15 ubuntu-linux dhclient[1518]: DHCPDISCOVER on wwx001e101f0000 to 255.255.255.255 port 67 interval 3 (xid=0x54674120)
Jul 24 22:50:15 ubuntu-linux sh[1500]: DHCPDISCOVER on wwx001e101f0000 to 255.255.255.255 port 67 interval 3 (xid=0x54674120)
Jul 24 22:50:15 ubuntu-linux dhclient[1518]: DHCPREQUEST of 100.64.25.234 on wwx001e101f0000 to 255.255.255.255 port 67 (xid=0x20416754)
Jul 24 22:50:15 ubuntu-linux sh[1500]: DHCPREQUEST of 100.64.25.234 on wwx001e101f0000 to 255.255.255.255 port 67 (xid=0x20416754)
Jul 24 22:50:15 ubuntu-linux dhclient[1518]: DHCPOFFER of 100.64.25.234 from 100.64.25.233
Jul 24 22:50:15 ubuntu-linux sh[1500]: DHCPOFFER of 100.64.25.234 from 100.64.25.233
Jul 24 22:50:15 ubuntu-linux dhclient[1518]: DHCPACK of 100.64.25.234 from 100.64.25.233
Jul 24 22:50:15 ubuntu-linux sh[1500]: DHCPACK of 100.64.25.234 from 100.64.25.233
Jul 24 22:50:15 ubuntu-linux dhclient[1518]: bound to 100.64.25.234 -- renewal in 249600 seconds.
Jul 24 22:50:15 ubuntu-linux sh[1500]: bound to 100.64.25.234 -- renewal in 249600 seconds.
Jul 24 22:50:15 ubuntu-linux systemd[1]: Reloading OpenBSD Secure Shell server.
Jul 24 22:50:15 ubuntu-linux systemd[1]: Reloaded OpenBSD Secure Shell server.
Jul 24 22:50:15 ubuntu-linux systemd[1]: Reloading.
Jul 24 22:50:19 ubuntu-linux systemd[1]: Started USB_ModeSwitch_1-2:1.0.
ifconfig-a：
wwx001e101f0000: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 100.64.119.246 netmask 255.255.255.252 broadcast 100.64.119.247
inet6 fe80::21e:10ff:fe1f:0 prefixlen 64 scopeid 0x20<link>
ether 00:1e:10:1f:00:00 txqueuelen 1000 (Ethernet)
RX packets 2 bytes 636 (636.0 B)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 24 bytes 2692 (2.6 KB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
但是，如果我因任何原因拔掉电源插头并重新连接调制解调器，它就会停止工作。
现在我要拔下并重新连接调制解调器：
Jul 24 22:53:47 ubuntu-linux kernel: [ 364.823156] ------------[ cut here ]------------
Jul 24 22:53:47 ubuntu-linux kernel: [ 364.823176] WARNING: CPU: 1 PID: 46 at /build/linux-Fk60NP/linux-4.10.0/drivers/usb/host/ehci-hcd.c:1053 ehci_endpoint_reset+0xfc/0x120
Jul 24 22:53:47 ubuntu-linux kernel: [ 364.823176] clear_halt for a busy endpoint
Jul 24 22:53:47 ubuntu-linux kernel: [ 364.823177] Modules linked in: huawei_cdc_ncm cdc_wdm cdc_ncm option usbnet usb_wwan mii usbserial uas usb_storage gpio_ich ppdev x86_pkg_temp_thermal snd_intel8x0 coretemp snd_ac97_codec ac97_bus uvcvideo intel_rapl_perf videobuf2_vmalloc snd_pcm videobuf2_memops snd_timer videobuf2_v4l2 videobuf2_core input_leds snd videodev soundcore serio_raw media lpc_ich sbs shpchp pvpanic sbshc parport_pc parport mac_hid ib_iser rdma_cm iw_cm ib_cm ib_core configfs iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi ip_tables x_tables autofs4 btrfs raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq libcrc32c raid1 raid0 multipath linear crct10dif_pclmul crc32_pclmul ghash_clmulni_intel pcbc aesni_intel aes_x86_64 crypto_simd glue_helper cryptd psmouse ahci libahci pata_acpi
Jul 24 22:53:47 ubuntu-linux kernel: [ 364.823227] virtio_net fjes
Jul 24 22:53:47 ubuntu-linux kernel: [ 364.823233] CPU: 1 PID: 46 Comm: kworker/1:1 Not tainted 4.10.0-19-generic #21-Ubuntu
Jul 24 22:53:47 ubuntu-linux kernel: [ 364.823234] Hardware name: Parallels Software International Inc. Parallels Virtual Platform/Parallels Virtual Platform, BIOS 12.1.1 (41491) 11/15/2016
Jul 24 22:53:47 ubuntu-linux kernel: [ 364.823240] Workqueue: events usbnet_deferred_kevent [usbnet]
Jul 24 22:53:47 ubuntu-linux kernel: [ 364.823242] Call Trace:
Jul 24 22:53:47 ubuntu-linux kernel: [ 364.823252] dump_stack+0x63/0x81
Jul 24 22:53:47 ubuntu-linux kernel: [ 364.823256] __warn+0xcb/0xf0
Jul 24 22:53:47 ubuntu-linux kernel: [ 364.823257] warn_slowpath_fmt+0x5f/0x80
Jul 24 22:53:47 ubuntu-linux kernel: [ 364.823264] ? usb_control_msg+0xec/0x120
Jul 24 22:53:47 ubuntu-linux kernel: [ 364.823267] ehci_endpoint_reset+0xfc/0x120
Jul 24 22:53:47 ubuntu-linux kernel: [ 364.823269] usb_hcd_reset_endpoint+0x25/0x60
Jul 24 22:53:47 ubuntu-linux kernel: [ 364.823271] usb_clear_halt+0x8b/0xb0
Jul 24 22:53:47 ubuntu-linux kernel: [ 364.823274] usbnet_deferred_kevent+0x10f/0x370 [usbnet]
Jul 24 22:53:47 ubuntu-linux kernel: [ 364.823283] ? __schedule+0x23b/0x6f0
Jul 24 22:53:47 ubuntu-linux kernel: [ 364.823286] process_one_work+0x1fc/0x4b0
Jul 24 22:53:47 ubuntu-linux kernel: [ 364.823288] worker_thread+0x4b/0x500
Jul 24 22:53:47 ubuntu-linux kernel: [ 364.823293] kthread+0x101/0x140
Jul 24 22:53:47 ubuntu-linux kernel: [ 364.823294] ? process_one_work+0x4b0/0x4b0
Jul 24 22:53:47 ubuntu-linux kernel: [ 364.823297] ? kthread_create_on_node+0x60/0x60
Jul 24 22:53:47 ubuntu-linux kernel: [ 364.823301] ret_from_fork+0x2c/0x40
Jul 24 22:53:47 ubuntu-linux kernel: [ 364.823302] ---[ end trace a2439ebdff9d582d ]---
Jul 24 22:53:48 ubuntu-linux kernel: [ 364.949036] usb 1-2: USB disconnect, device number 4
Jul 24 22:53:48 ubuntu-linux kernel: [ 364.949175] option1 ttyUSB0: GSM modem (1-port) converter now disconnected from ttyUSB0
Jul 24 22:53:48 ubuntu-linux kernel: [ 364.949186] option 1-2:1.0: device disconnected
Jul 24 22:53:48 ubuntu-linux kernel: [ 364.949256] option1 ttyUSB1: GSM modem (1-port) converter now disconnected from ttyUSB1
Jul 24 22:53:48 ubuntu-linux kernel: [ 364.949261] option 1-2:1.1: device disconnected
Jul 24 22:53:48 ubuntu-linux kernel: [ 364.949297] huawei_cdc_ncm 1-2:1.2 wwx001e101f0000: unregister 'huawei_cdc_ncm' usb-0000:00:1d.7-2, Huawei CDC NCM device
Jul 24 22:53:48 ubuntu-linux dhclient[1599]: receive_packet failed on wwx001e101f0000: Network is down
Jul 24 22:53:48 ubuntu-linux systemd[1]: Stopping ifup for wwx001e101f0000...
Jul 24 22:53:48 ubuntu-linux systemd[1]: Reloading.
Jul 24 22:53:48 ubuntu-linux dhclient[1710]: Killed old client process
Jul 24 22:53:48 ubuntu-linux ifdown[1668]: Killed old client process
Jul 24 22:53:49 ubuntu-linux dhclient[1710]: Internet Systems Consortium DHCP Client 4.3.5
Jul 24 22:53:49 ubuntu-linux ifdown[1668]: Internet Systems Consortium DHCP Client 4.3.5
Jul 24 22:53:49 ubuntu-linux dhclient[1710]: Copyright 2004-2016 Internet Systems Consortium.
Jul 24 22:53:49 ubuntu-linux ifdown[1668]: Copyright 2004-2016 Internet Systems Consortium.
Jul 24 22:53:49 ubuntu-linux dhclient[1710]: All rights reserved.
Jul 24 22:53:49 ubuntu-linux ifdown[1668]: All rights reserved.
Jul 24 22:53:49 ubuntu-linux dhclient[1710]: For info, please visit https://www.isc.org/software/dhcp/
Jul 24 22:53:49 ubuntu-linux ifdown[1668]: For info, please visit https://www.isc.org/software/dhcp/
Jul 24 22:53:49 ubuntu-linux dhclient[1710]:
Jul 24 22:53:49 ubuntu-linux dhclient[1710]: Error getting hardware address for "wwx001e101f0000": No such device
Jul 24 22:55:14 ubuntu-linux kernel: [ 451.044516] Buffer I/O error on dev sr1, logical block 18170, async page read
Jul 24 22:55:20 ubuntu-linux systemd[1]: Started USB_ModeSwitch_1-2:1.0.