1

I'm on a Lenovo Thinkpad X1 Carbon (early 2016) that came with a built-in Sierra EM7455 card. I'd like to make the switch to Linux but I'm currently unable to make use of the mobile broadband connection. In contrast to other questions asked regarding that piece of hardware, I have no trouble connecting via NetworkManager (using a live cd) - however, the interface never gets assigned a valid IP address, just a local address. I'm using the German provider Congstar. Any suggestions where to look or what I can do about this?

  • Is there a listing for it in Additional Drivers? – Android Dev Aug 11 '16 at 20:59
  • What do you mean by "local address"? Something in the 169.x.x.x link-local range, or an RFC-1918 private address (192.168.x.x, 10.x.x.x, or something in 172.16.x.x-172.31.x.x) ? – user4556274 Aug 11 '16 at 21:05
  • Thanks for your replies - I always get an IP address starting with 10.x.x.x if that helps. As for the additional drivers question: I'll check that right away. – hyperlord Aug 11 '16 at 22:00
  • Just to follow up: there is only one entry in "Additional Drivers" but that is for Intel CPU (intel-microcode firmware). – hyperlord Aug 11 '16 at 22:20
  • Ok one more thing to add to the confusion: when using a 16.04.1 live cd image, I cannot create the broadband connection in the network manager UI. I can configure all the steps but after that I cannot select the connection in teh dropdown field within the mobile broadband UI. Using a daily live CD (16.10), this actually works but then the problem with the price ip (10.x.x.x) happens. The problem is, I cannot simply wipe the machine and install ubuntu if the broadband does not work since I need the machine for work - that's why I'm testing with live-cd images via USB stick. – hyperlord Aug 11 '16 at 22:30
0

I have a 3rd gen X1 Carbon and WWAN(3G/LTE) works perfectly with 14.04. I actually work every day on LTE, as my company corporate network is very restricted. Modem is Sierra Wireless EM7345 4G LTE . I don't have a real solution for you, but 2 options to test come to my mind:

  1. try live CD with 14.04
  2. try dual boot with 16.04

If it works with 14.04 live CD - then there is an issue with 16.04. If it does not work, then try option 2).

0

First, test it in Windows if possible to make sure your SIM card actually is compatible with the laptop -- I've had compatibility issues before.

You need to pull in some packages from Yakkety Yak to Xenial -- specifically, libqmi 1.16.0, libmbim 1.14.0, and modemmanager 1.6.0. Upgrade those, reboot, and the modem should work. It does on mine. If you need more detailed instructions I'll provide them later when I'm not writing from my phone.

One caveat -- suspending and resuming the laptop kills the modem until your next reboot.

EDIT: If you're running a Yakkety live USB, then surprisingly the modem probably won't work, because the Yakkety kernel (4.4.0-9135) lacks a critical kernel patch that the EM7455 requires. The latest Xenial kernel (4.4.0-36) DOES have this patch, backported from mainline. You need to run Xenial and pull in the abovementioned Yakkety packages.

  • Thanks for your replay - I just added more information from both Windows and Linux/Gnome in an additional answer (would have been too long for a comment). So on Windows, things work fine - comparing the network settings with those on Linux, it appears that on Linux there is no IPv6 configuration applied. Do you have an idea what might cause this and how to work around it? – hyperlord Sep 8 '16 at 7:34
  • @hyperlord I don't think anyone can be sure of what's going on, but if you ask me -- my guess is you're encountering the same issue that Nathaniel Nutter experienced on Fedora, which is that all the IP addresses and routing appears fine but there's no data. (I'm ignoring the IPv6 stuff since it appears to be a red herring; I don't use IPv6 and everything works for me.) In his case upgrading to a newer kernel solved it. – djao Sep 10 '16 at 1:02
0

sorry for not getting back to this issue sooner but thanks for all the input (especially @djao and @Zlatko).

I have no problem connecting with the same SIM card using Windows 10. I have investigated this a bit further and apparently I can actually connect with a 16.04 LTS live CD just fine. At least there seems to be some kind of connection and I also get an IP address via DHCP as well as a gateway address but I am unable to connet to the outside world. So on Linux I get this:

ifconfig:

enp0s31f6 Link encap:Ethernet  HWaddr 54:ee:75:98:13:6e  
      UP BROADCAST MULTICAST  MTU:1500  Metric:1
      RX packets:0 errors:0 dropped:0 overruns:0 frame:0
      TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
      collisions:0 txqueuelen:1000 
      RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)
      Interrupt:16 Memory:f1200000-f1220000 

lo    Link encap:Local Loopback  
      inet addr:127.0.0.1  Mask:255.0.0.0
      inet6 addr: ::1/128 Scope:Host
      UP LOOPBACK RUNNING  MTU:65536  Metric:1
      RX packets:517 errors:0 dropped:0 overruns:0 frame:0
      TX packets:517 errors:0 dropped:0 overruns:0 carrier:0
      collisions:0 txqueuelen:1 
      RX bytes:38626 (38.6 KB)  TX bytes:38626 (38.6 KB)

wlp4s0 Link encap:Ethernet  HWaddr 44:85:00:30:12:63  
      UP BROADCAST MULTICAST  MTU:1500  Metric:1
      RX packets:0 errors:0 dropped:0 overruns:0 frame:0
      TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
      collisions:0 txqueuelen:1000 
      RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)

wwp0s20f0u2i12 Link encap:Ethernet  HWaddr 82:83:4b:ab:49:52  
      inet addr:10.132.103.154  Bcast:10.132.103.155 Mask:255.255.255.252
      UP BROADCAST RUNNING NOARP MULTICAST  MTU:1500  Metric:1
      RX packets:0 errors:0 dropped:0 overruns:0 frame:0
      TX packets:51 errors:0 dropped:0 overruns:0 carrier:0
      collisions:0 txqueuelen:1000 
      RX bytes:0 (0.0 B)  TX bytes:4303 (4.3 KB)

As you can see, I have an 10.x.x.x IP on the wwp0s20f0u2i12 device. The routing table looks like this:

route -n:

Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         10.132.103.153  0.0.0.0         UG    700    0        0 wwp0s20f0u2i12
10.132.103.152  0.0.0.0         255.255.255.252 U     700    0        0 wwp0s20f0u2i12
169.254.0.0     0.0.0.0         255.255.0.0     U     1000   0        0 wwp0s20f0u2i12

route -n:
Kernel IPv6 routing table
Destination                    Next Hop                   Flag Met Ref Use If
::/0                           ::                         !n   -1  1     1 lo
::1/128                        ::                         Un   0   3     4 lo
::/0                           ::                         !n   -1  1     1 lo

On Windows 10 the data looks like this (sorry, it's a German installation):

Windows-IP-Konfiguration


Ethernet-Adapter Ethernet:

   Medienstatus. . . . . . . . . . . : Medium getrennt
   Verbindungsspezifisches DNS-Suffix: 

Drahtlos-LAN-Adapter LAN-Verbindung* 2:

   Medienstatus. . . . . . . . . . . : Medium getrennt
   Verbindungsspezifisches DNS-Suffix: 

Mobiler Breitbandadapter Mobilfunk:

   Verbindungsspezifisches DNS-Suffix: 
   IPv6-Adresse. . . . . . . . . . . : 2a01:598:80a0:ac2f:310f:dcc0:767e:79
   IPv6-Adresse. . . . . . . . . . . : 2a01:598:80a0:ac2f:6063:db5:32b:a774
   Temporäre IPv6-Adresse. . . . . . : 2a01:598:80a0:ac2f:d90:e51a:6ee4:1721
   Verbindungslokale IPv6-Adresse  . : fe80::310f:dcc0:767e:79%22
   IPv4-Adresse  . . . . . . . . . . : 10.120.86.84
   Subnetzmaske  . . . . . . . . . . : 255.255.255.248
   Standardgateway . . . . . . . . . : 2a01:598:80a0:ac2f:244e:b30a:d6e7:d2f5
                                   fe80::244e:b30a:d6e7:d2f5%22
                                   10.120.86.85

Ethernet-Adapter Bluetooth-Netzwerkverbindung:

   Medienstatus. . . . . . . . . . . : Medium getrennt
   Verbindungsspezifisches DNS-Suffix: 

Drahtlos-LAN-Adapter WLAN:

   Medienstatus. . . . . . . . . . . : Medium getrennt
   Verbindungsspezifisches DNS-Suffix: fritz.box

Tunneladapter LAN-Verbindung* 13:

   Verbindungsspezifisches DNS-Suffix: 
   IPv6-Adresse. . . . . . . . . . . : 2001:0:5ef5:79fd:1408:8b1f:af44:94a0
   Verbindungslokale IPv6-Adresse  . : fe80::1408:8b1f:af44:94a0%8
   Standardgateway . . . . . . . . . : 

Tunneladapter isatap.{FD0ADE13-38D6-4003-88E7-7859324C8860}:

   Medienstatus. . . . . . . . . . . : Medium getrennt
   Verbindungsspezifisches DNS-Suffix: 

And the routing table on Windows:

netstat -rn
===========================================================================
Schnittstellenliste
 17...54 ee 75 98 13 6e ......Intel(R) Ethernet Connection I219-V
 19...44 85 00 30 12 64 ......Microsoft Wi-Fi Direct Virtual Adapter
 22...98 85 9c 57 5a 5e ......Sierra Wireless EM7455 Qualcomm Snapdragon X7 LTE-A
  6...44 85 00 30 12 67 ......Bluetooth Device (Personal Area Network)
 21...3a f5 d1 8c 1b 5b ......Intel(R) Dual Band Wireless-AC 8260
  1...........................Software Loopback Interface 1
  8...00 00 00 00 00 00 00 e0 Microsoft Teredo Tunneling Adapter
 11...00 00 00 00 00 00 00 e0 Microsoft ISATAP Adapter #3
===========================================================================

IPv4-Routentabelle
===========================================================================
Aktive Routen:
     Netzwerkziel    Netzwerkmaske          Gateway    Schnittstelle Metrik
          0.0.0.0          0.0.0.0     10.120.86.85     10.120.86.84    311
     10.120.86.80  255.255.255.248   Auf Verbindung      10.120.86.84    311
     10.120.86.84  255.255.255.255   Auf Verbindung      10.120.86.84    311
     10.120.86.87  255.255.255.255   Auf Verbindung      10.120.86.84    311
        127.0.0.0        255.0.0.0   Auf Verbindung         127.0.0.1    331
        127.0.0.1  255.255.255.255   Auf Verbindung         127.0.0.1    331
  127.255.255.255  255.255.255.255   Auf Verbindung         127.0.0.1    331
        224.0.0.0        240.0.0.0   Auf Verbindung         127.0.0.1    331
        224.0.0.0        240.0.0.0   Auf Verbindung      10.120.86.84    311
  255.255.255.255  255.255.255.255   Auf Verbindung         127.0.0.1    331
  255.255.255.255  255.255.255.255   Auf Verbindung      10.120.86.84    311
===========================================================================
Ständige Routen:
  Keine

IPv6-Routentabelle
===========================================================================
Aktive Routen:
 If Metrik Netzwerkziel             Gateway
 22    311 ::/0                     2a01:598:80a0:ac2f:244e:b30a:d6e7:d2f5
 22    311 ::/0                     fe80::244e:b30a:d6e7:d2f5
  1    331 ::1/128                  Auf Verbindung
  8    331 2001::/32                Auf Verbindung
  8    331 2001:0:5ef5:79fd:1408:8b1f:af44:94a0/128
                                    Auf Verbindung
 22    311 2a01:598:80a0:ac2f::/64  Auf Verbindung
 22    311 2a01:598:80a0:ac2f:d90:e51a:6ee4:1721/128
                                    Auf Verbindung
 22    311 2a01:598:80a0:ac2f:310f:dcc0:767e:79/128
                                    Auf Verbindung
 22    311 2a01:598:80a0:ac2f:6063:db5:32b:a774/128
                                    Auf Verbindung
 22    311 fe80::/64                Auf Verbindung
  8    331 fe80::/64                Auf Verbindung
  8    331 fe80::1408:8b1f:af44:94a0/128
                                    Auf Verbindung
 22    311 fe80::310f:dcc0:767e:79/128
                                    Auf Verbindung
  1    331 ff00::/8                 Auf Verbindung
  8    331 ff00::/8                 Auf Verbindung
 22    311 ff00::/8                 Auf Verbindung
===========================================================================
Ständige Routen:
  Keine

So on Windows the IPv4 address is also from the 10.x.x.x range but I also get IPv6 addresses. Maybe this causes the issue on Linux since there is no IPv6 configuration setup (if I don't misread the linux output). Any suggestions what might cause this or even better how to fix this? Thanks!

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.