Mobile broadband SIM doesn't work but does on same machine booted into Windows

[Rob Davis]

I am trying to use a mobile broadband sim with my TabletPC running Ubuntu 18.04, but it doesn't work, I get: "Connection Failed: Activation of network connection failed" when trying to connect with it. HOWEVER, if I boot this same TabletPC into Windows 10, the sim works fine. So it is not a problem with the SIM nor a problem the TabletPC hardware. It is a problem with Ubuntu.

Can I ask what testing/Quality Assurance (QA) you did on Ubuntu for mobile broadband and where your testing records are kept?

Further details here:
https://askubuntu.com/questions/1079689/mobile-broadband-sim-doesnt-work-with-ubuntu-18-04-but-does-work-in-same-device

"I have a Panasonic FZ-G1 MkIII Toughpad touchscreen tablet PC which is based on an x86-64bit Intel® Core™ i5-5300U CPU @ 2.30GHz, with 4Gb RAM.

This is dual-booted with Windows 10 Pro 64bit (build 1803) and Ubuntu 18.04.1 LTS 64bit.

The mobile sim is a standard giffgaff sim which works fine in Windows on this machine - it is recognised and internet access via it works, detected as LTE (4G). So this proves that the sim is working correctly with the WLAN modem hardware in this tablet.

However, when the same tablet is booted into Ubuntu 18.04.1 LTS 64bit, the same sim that worked in the Windows partition, does not work in Ubuntu. Error message: "Connection Failed: Activation of network connection failed" pops up when attempting connection via Settings. "

[Ubuntu Foundations Team Bug Bot (crichton)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. It seems that your bug report is not filed about a specific source package though, rather it is just filed against Ubuntu in general. It is important that bug reports be filed about source packages so that people interested in the package can find the bugs about it. You can find some hints about determining what package your bug might be about at https://wiki.ubuntu.com/Bugs/FindRightPackage. You might also ask for help in the #ubuntu-bugs irc channel on Freenode.

To change the source package that this bug is filed about visit https://bugs.launchpad.net/ubuntu/+bug/1806407/+editstatus and add the package name in the text box next to the word Package.

[This is an automated message. I apologize if it reached you inappropriately; please just reply to this message indicating so.]

[Diorama Yuanito (dioramayuanito)]

in my Ubuntu-MATE 18.04.2, all my three modems after connect to provider but browser says it cannot Resolve domains. in /var/log/syslog somehow appears 'degraded nameserver' or something. But Wifi connection works smooth. i have Ubuntu-MATE 16.04.2 and my modems work fine.

How to fix this bug?

[Diorama Yuanito (dioramayuanito)]

i'm using Mobile Broadband in Network Manager applet to make a connection from an usb modem.

[Diorama Yuanito (dioramayuanito)]

Mar 22 15:46:59 mate-Lenovo-ideapad-D330-10IGM systemd-resolved[576]: Using degraded feature set (TCP) for DNS server 112.215.71.243.
Mar 22 15:47:03 mate-Lenovo-ideapad-D330-10IGM systemd-resolved[576]: Using degraded feature set (UDP) for DNS server 112.215.198.254.
Mar 22 15:47:05 mate-Lenovo-ideapad-D330-10IGM systemd-resolved[576]: Using degraded feature set (UDP) for DNS server 112.215.71.243.
Mar 22 15:47:08 mate-Lenovo-ideapad-D330-10IGM systemd-resolved[576]: Using degraded feature set (TCP) for DNS server 112.215.71.243.
Mar 22 15:47:08 mate-Lenovo-ideapad-D330-10IGM systemd-resolved[576]: Using degraded feature set (TCP) for DNS server 112.215.198.254.
Mar 22 15:47:14 mate-Lenovo-ideapad-D330-10IGM systemd-resolved[576]: Using degraded feature set (UDP) for DNS server 112.215.71.243.
Mar 22 15:47:14 mate-Lenovo-ideapad-D330-10IGM systemd-resolved[576]: Using degraded feature set (UDP) for DNS server 112.215.198.254.

[Diorama Yuanito (dioramayuanito)]

still no luck when i change /etc/NetworkManager/NetworkManager.conf to bypass system-resolved with

[main]
dns=default

and i already try replace system-resolved with dnsmasq with NetworkManager.conf

[main]
dns=dnsmasq

still no lock with those things

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Diorama Yuanito (dioramayuanito)]

mate@mate-Lenovo-YOGA-330-11IGM:~$ dig google.com

; <<>> DiG 9.11.3-1ubuntu1.5-Ubuntu <<>> google.com
;; global options: +cmd
;; connection timed out; no servers could be reached
mate@mate-Lenovo-YOGA-330-11IGM:~$

[Rob Davis (therobyouknow)]

Thrilled to confirm that this now works in Ubuntu 20.04.1 LTS 64bit I have checked today.

Thank you so, so much.

Will update with more details on: https://askubuntu.com/questions/1079689/mobile-broadband-sim-doesnt-work-with-ubuntu-18-04-but-does-work-in-same-device

SIM hardware is detected following and it's then just a case of going through the wizard setup dialog Windows that is displayed after you click on your mobile networking symbol on top right or from the top right drop down.