<div dir="ltr"><div>I'm having a fight with a USB modem that I'm currently losing. Badly. I'm hoping members of this list can help me turn the tide! I have the following script that works fine on my desktop Linux system, but fails to obtain an IP address on an embedded target: #!/bin/bash set -euo pipefail export PATH=/home/embedded-dev/bin:$PATH if [[ "$(hostname)" = "embedded-dev" ]]; then IFACE=wwp0s21f0u3u4i8 else IFACE=wwp0s26u1u2i8 fi qmicli -p -d /dev/cdc-wdm0 --wds-start-network="<a href="http://fast.t-mobile.com" target="_blank">fast.t-mobile.com</a>" --client-no-release-cid sleep 1 qmicli -p -d /dev/cdc-wdm0 --wds-get-current-settings sleep 1 ip link set ${IFACE} up killall dhclient || true killall -9 dhclient || true sleep 1 dhclient -v ${IFACE} </div>For reference, here's the uname -a output for the target machine: root@embedded-dev $ uname -a Linux embedded-dev 4.1.13-abl #2 SMP Mon Aug 15 09:54:15 EDT 2016 x86_64 GNU/Linux <div><div> </div><div>I've got libqmi-1.16.0 on this board: root@embedded-dev $ qmicli --version qmicli 1.16.0 Copyright (C) 2015 Aleksander Morgado License GPLv2+: GNU GPL version 2 or later <<a href="http://gnu.org/licenses/gpl-2.0.html" target="_blank">http://gnu.org/licenses/gpl-2.0.html</a>> This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. And this version of dhclient: root@embedded-dev $ dhclient --version isc-dhclient-4.3.2 And here's the output that gets logged when I plug the device into a USB port: root@embedded-dev $ dmesg [ 478.807167] usb 1-3.4: new high-speed USB device number 7 using xhci_hcd [ 478.893117] usb 1-3.4: config 1 has an invalid interface number: 9 but max is 0 [ 478.893125] usb 1-3.4: config 1 has no interface number 0 [ 478.894156] usb 1-3.4: New USB device found, idVendor=1199, idProduct=0fff [ 478.894160] usb 1-3.4: New USB device strings: Mfr=1, Product=2, SerialNumber=3 [ 478.894163] usb 1-3.4: Product: AirCard 340U [ 478.894166] usb 1-3.4: Manufacturer: Sierra Wireless, Incorporated [ 478.894169] usb 1-3.4: SerialNumber: 013323000518432 [ 478.896117] usb-storage 1-3.4:1.9: USB Mass Storage device detected [ 478.897287] usb-storage: probe of 1-3.4:1.9 failed with error -5 [ 482.179390] usb 1-3.4: USB disconnect, device number 7 [ 482.460787] usb 1-3.4: new high-speed USB device number 8 using xhci_hcd [ 482.546811] usb 1-3.4: config 1 has an invalid interface number: 8 but max is 4 [ 482.546819] usb 1-3.4: config 1 has an invalid interface number: 9 but max is 4 [ 482.546822] usb 1-3.4: config 1 has no interface number 1 [ 482.546825] usb 1-3.4: config 1 has no interface number 4 [ 482.547806] usb 1-3.4: New USB device found, idVendor=1199, idProduct=9051 [ 482.547811] usb 1-3.4: New USB device strings: Mfr=1, Product=2, SerialNumber=3 [ 482.547814] usb 1-3.4: Product: AirCard 340U [ 482.547817] usb 1-3.4: Manufacturer: Sierra Wireless, Incorporated [ 482.547819] usb 1-3.4: SerialNumber: 013323000518432 [ 482.550472] qcserial 1-3.4:1.2: Qualcomm USB modem converter detected [ 482.551133] usb 1-3.4: Qualcomm USB modem converter now attached to ttyUSB0 [ 482.551683] qcserial 1-3.4:1.3: Qualcomm USB modem converter detected [ 482.552020] usb 1-3.4: Qualcomm USB modem converter now attached to ttyUSB1 [ 482.552692] qmi_wwan 1-3.4:1.8: cdc-wdm0: USB WDM device [ 482.553086] qmi_wwan 1-3.4:1.8 wwan0: register 'qmi_wwan' at usb-0000:00:15.0-3.4, WWAN/QMI device, 0e:b8:0a:b2:69:43 [ 482.554014] usb-storage 1-3.4:1.9: USB Mass Storage device detected [ 482.555115] scsi host5: usb-storage 1-3.4:1.9 [ 482.557113] qcserial 1-3.4:1.0: Qualcomm USB modem converter detected [ 482.557430] usb 1-3.4: Qualcomm USB modem converter now attached to ttyUSB2 [ 482.571196] qmi_wwan 1-3.4:1.8 wwp0s21f0u3u4i8: renamed from wwan0 [ 483.545931] scsi 5:0:0:0: Direct-Access Aircard Disk Drive 1.00 PQ: 0 ANSI: 2 [ 483.548424] sd 5:0:0:0: Attached scsi generic sg0 type 0 [ 483.550934] sd 5:0:0:0: [sda] Attached SCSI removable disk </div><div> </div><div>When I run the script on the target, I see the following output: root@embedded-dev $ ./start-net.sh [/dev/cdc-wdm0] Network started Packet data handle: '1143419264' [/dev/cdc-wdm0] Client ID not released: Service: 'wds' CID: '1' [/dev/cdc-wdm0] Current settings retrieved: IP Family: IPv4 IPv4 address: 21.87.88.78 IPv4 subnet mask: 255.255.255.252 IPv4 gateway address: 21.87.88.77 IPv4 primary DNS: 10.177.0.34 IPv4 secondary DNS: 10.177.0.210 MTU: 1430 Domains: none Internet Systems Consortium DHCP Client 4.3.2 Copyright 2004-2015 Internet Systems Consortium. All rights reserved. For info, please visit <a href="https://www.isc.org/software/dhcp/">https://www.isc.org/software/dhcp/</a> Listening on LPF/wwp0s21f0u3u4i8/0e:b8:0a:b2:69:43 Sending on LPF/wwp0s21f0u3u4i8/0e:b8:0a:b2:69:43 Sending on Socket/fallback DHCPDISCOVER on wwp0s21f0u3u4i8 to 255.255.255.255 port 67 interval 5 DHCPDISCOVER on wwp0s21f0u3u4i8 to 255.255.255.255 port 67 interval 10 DHCPDISCOVER on wwp0s21f0u3u4i8 to 255.255.255.255 port 67 interval 17 DHCPDISCOVER on wwp0s21f0u3u4i8 to 255.255.255.255 port 67 interval 9 DHCPDISCOVER on wwp0s21f0u3u4i8 to 255.255.255.255 port 67 interval 8 DHCPDISCOVER on wwp0s21f0u3u4i8 to 255.255.255.255 port 67 interval 12 No DHCPOFFERS received. No working leases in persistent database - sleeping. </div><div>My desktop machine is running Fedora 23: [~$:999] uname -a Linux localhost.localdomain 4.4.9-300.fc23.x86_64 #1 SMP Wed May 4 23:56:27 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux </div><div>It's also using libqmi-1.16.0, and a slightly different version of dhclient: [~$:1017] dhclient --version isc-dhclient-4.3.3-P1 When I plug the modem into this machine and run the same script, it emits the following: [~$:1014] sudo ./start-net.sh [sudo] password for demo: [/dev/cdc-wdm0] Network started Packet data handle: '1143422144' [/dev/cdc-wdm0] Client ID not released: Service: 'wds' CID: '3' [/dev/cdc-wdm0] Current settings retrieved: IP Family: IPv4 IPv4 address: 26.173.92.29 IPv4 subnet mask: 255.255.255.252 IPv4 gateway address: 26.173.92.30 IPv4 primary DNS: 10.177.0.34 IPv4 secondary DNS: 10.177.0.210 MTU: 1430 Domains: none dhclient: no process found dhclient: no process found Internet Systems Consortium DHCP Client 4.3.3-P1 Copyright 2004-2016 Internet Systems Consortium. All rights reserved. For info, please visit <a href="https://www.isc.org/software/dhcp/">https://www.isc.org/software/dhcp/</a> Listening on LPF/wwp0s26u1u2i8/7a:b0:a0:37:07:94 Sending on LPF/wwp0s26u1u2i8/7a:b0:a0:37:07:94 Sending on Socket/fallback DHCPDISCOVER on wwp0s26u1u2i8 to 255.255.255.255 port 67 interval 5 (xid=0xc4f9f664) DHCPREQUEST on wwp0s26u1u2i8 to 255.255.255.255 port 67 (xid=0xc4f9f664) DHCPOFFER from 26.173.92.30 DHCPACK from 26.173.92.30 (xid=0xc4f9f664) bound to 26.173.92.29 -- renewal in 3212 seconds. </div><div>After that, I have a glorious LTE connection to the Interwebs! But I've had no luck getting it to work on the embedded device. Can anybody recommend steps to troubleshoot this? </div><div>Some things I've tried so far include: </div><div>1. Upgrading from libqmi-1.12.2 to 1.16.0. This allowed me to use --wds-get-current-settings, but dhclient still failed to obtain an IP address. </div><div> 2. Manually configure the connection based on the settings reported by qmicli -p -d /dev/cdc-wdm0 --wds-get-current-settings. I was unable to get this to work, neither on the target, nor on my desktop machine. The IP address, routing table and /etc/resolv.conf looked correct to me, but... I'm not very familiar with the commands ip addr, ip route, ip link, etc, so I probably made some mistakes. When other posts on this mailing list suggested using dhclient, for similar situations, I didn't pursue manual configuration any further. If somebody can tell me the correct commands needed to manually configure the connection, I can check this, if it helps. </div><div>3. Applying the patches mentioned in this mailing list thread: <a href="https://lists.freedesktop.org/archives/libqmi-devel/2015-December/001477.html">https://lists.freedesktop.org/archives/libqmi-devel/2015-December/001477.html</a> </div><div>I'm about out of ideas at this point. I've seen other posts on this mailing list that mention using tcpdump to sniff packets, but I'm not sure I'd know which interface to capture on, or how to interpret the traces. Any hints/tips along those lines will be much appreciated! </div><div>One other thing that may be worth mentioning is that the kernel log output upon inserting the modem into my desktop machine is more-or-less identical, except for a few errors that get emitted: [83474.891190] usb 1-1.2: new high-speed USB device number 13 using ehci-pci [83474.977240] usb 1-1.2: config 1 has an invalid interface number: 9 but max is 0 [83474.977247] usb 1-1.2: config 1 has no interface number 0 [83474.978607] usb 1-1.2: New USB device found, idVendor=1199, idProduct=0fff [83474.978616] usb 1-1.2: New USB device strings: Mfr=1, Product=2, SerialNumber=3 [83474.978622] usb 1-1.2: Product: AirCard 340U [83474.978627] usb 1-1.2: Manufacturer: Sierra Wireless, Incorporated [83474.978631] usb 1-1.2: SerialNumber: 013323000518432 [83474.980975] usb-storage 1-1.2:1.9: USB Mass Storage device detected [83474.982028] usb-storage: probe of 1-1.2:1.9 failed with error -5 [83478.556940] usb 1-1.2: USB disconnect, device number 13 [83478.811958] usb 1-1.2: new high-speed USB device number 14 using ehci-pci [83478.898017] usb 1-1.2: config 1 has an invalid interface number: 8 but max is 4 [83478.898024] usb 1-1.2: config 1 has an invalid interface number: 9 but max is 4 [83478.898027] usb 1-1.2: config 1 has no interface number 1 [83478.898030] usb 1-1.2: config 1 has no interface number 4 [83478.899477] usb 1-1.2: New USB device found, idVendor=1199, idProduct=9051 [83478.899483] usb 1-1.2: New USB device strings: Mfr=1, Product=2, SerialNumber=3 [83478.899487] usb 1-1.2: Product: AirCard 340U [83478.899490] usb 1-1.2: Manufacturer: Sierra Wireless, Incorporated [83478.899492] usb 1-1.2: SerialNumber: 013323000518432 [83478.901929] qcserial 1-1.2:1.2: Qualcomm USB modem converter detected [83478.902109] usb 1-1.2: Qualcomm USB modem converter now attached to ttyUSB0 [83478.902571] qcserial 1-1.2:1.3: Qualcomm USB modem converter detected [83478.902718] usb 1-1.2: Qualcomm USB modem converter now attached to ttyUSB1 [83478.903582] qmi_wwan 1-1.2:1.8: cdc-wdm0: USB WDM device [83478.903957] qmi_wwan 1-1.2:1.8 wwan0: register 'qmi_wwan' at usb-0000:00:1a.0-1.2, WWAN/QMI device, 32:5b:78:6c:82:3a [83478.904613] usb-storage 1-1.2:1.9: USB Mass Storage device detected [83478.905929] scsi host16: usb-storage 1-1.2:1.9 [83478.906604] qcserial 1-1.2:1.0: Qualcomm USB modem converter detected [83478.906769] usb 1-1.2: Qualcomm USB modem converter now attached to ttyUSB2 [83478.984865] qmi_wwan 1-1.2:1.8 wwp0s26u1u2i8: renamed from wwan0 [83479.455637] qcserial ttyUSB2: usb_wwan_indat_callback: resubmit read urb failed. (-2) [83479.455655] qcserial ttyUSB2: usb_wwan_indat_callback: resubmit read urb failed. (-2) [83479.455660] qcserial ttyUSB2: usb_wwan_indat_callback: resubmit read urb failed. (-2) [83479.455941] qcserial ttyUSB2: Qualcomm USB modem converter now disconnected from ttyUSB2 [83479.455974] qcserial 1-1.2:1.0: device disconnected [83479.911726] scsi 16:0:0:0: Direct-Access Aircard Disk Drive 1.00 PQ: 0 ANSI: 2 [83479.912912] sd 16:0:0:0: Attached scsi generic sg2 type 0 [83479.917020] sd 16:0:0:0: [sdb] Attached SCSI removable disk </div><div>Perhaps those resubmit read urb failed errors provide a clue as to why this device works on my desktop, but not the embedded device? </div><div>Thanks for your consideration, this has been driving me nuts for two weeks now... `:-] </div></div></div>