Comment 0 for bug 1803135

Hello,
I am working on Ubuntu 16.04 with the following details [1], which is a fresh installation on Thinkpad Carbon laptop.
Since day 1, I could not manage to use my home WLAN for things like wget, update packages etc.
Here is one example trying to install some package using my home WLAN [2], and instant output of trying to install the same package after switching to my Mobile data [3].

I do not see a reason why it should happen, specially when this works for my other personal laptop (DELL).

Any suggestions to dig it further is appreciated.

Many thanks,

[1]
**********************
$ uname -a
Linux X1-Carbon-6 4.19.0-041900rc4-lowlatency #201809162031 SMP PREEMPT Sun Sep 16 20:36:16 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux

[2]
*************************
$ sudo apt-get install python3-venv
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages were automatically installed and are no longer required:
  libgsoap8 libvncserver1 linux-headers-4.15.0-29
  linux-headers-4.15.0-29-generic linux-headers-4.4.0-135
  linux-headers-4.4.0-135-generic linux-image-4.15.0-29-generic
  linux-image-4.4.0-135-generic linux-image-extra-4.4.0-135-generic
  linux-modules-4.15.0-29-generic linux-modules-extra-4.15.0-29-generic
  linux-signed-image-4.4.0-135-generic
Use 'sudo apt autoremove' to remove them.
The following additional packages will be installed:
  python3.5-venv
The following NEW packages will be installed:
  python3-venv python3.5-venv
0 upgraded, 2 newly installed, 0 to remove and 8 not upgraded.
Need to get 7.104 B of archives.
After this operation, 39,9 kB of additional disk space will be used.
Do you want to continue? [Y/n] y
Err:1 http://security.ubuntu.com/ubuntu xenial-security/universe amd64 python3.5-venv amd64 3.5.2-2ubuntu0~16.04.4
  Temporary failure resolving 'de.archive.ubuntu.com'
Err:2 http://de.archive.ubuntu.com/ubuntu xenial/universe amd64 python3-venv amd64 3.5.1-3
  Temporary failure resolving 'de.archive.ubuntu.com'
Err:1 http://security.ubuntu.com/ubuntu xenial-security/universe amd64 python3.5-venv amd64 3.5.2-2ubuntu0~16.04.4
  Temporary failure resolving 'de.archive.ubuntu.com'
E: Failed to fetch http://security.ubuntu.com/ubuntu/pool/universe/p/python3.5/python3.5-venv_3.5.2-2ubuntu0~16.04.4_amd64.deb Temporary failure resolving 'de.archive.ubuntu.com'

E: Failed to fetch http://de.archive.ubuntu.com/ubuntu/pool/universe/p/python3-defaults/python3-venv_3.5.1-3_amd64.deb Temporary failure resolving 'de.archive.ubuntu.com'

E: Unable to fetch some archives, maybe run apt-get update or try with --fix-missing?

[3]
************************
$ sudo apt-get install python3-venv
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages were automatically installed and are no longer required:
  libgsoap8 libvncserver1 linux-headers-4.15.0-29
  linux-headers-4.15.0-29-generic linux-headers-4.4.0-135
  linux-headers-4.4.0-135-generic linux-image-4.15.0-29-generic
  linux-image-4.4.0-135-generic linux-image-extra-4.4.0-135-generic
  linux-modules-4.15.0-29-generic linux-modules-extra-4.15.0-29-generic
  linux-signed-image-4.4.0-135-generic
Use 'sudo apt autoremove' to remove them.
The following additional packages will be installed:
  python3.5-venv
The following NEW packages will be installed:
  python3-venv python3.5-venv
0 upgraded, 2 newly installed, 0 to remove and 8 not upgraded.
Need to get 7.104 B of archives.
After this operation, 39,9 kB of additional disk space will be used.
Do you want to continue? [Y/n] y
Get:1 http://de.archive.ubuntu.com/ubuntu xenial-updates/universe amd64 python3.5-venv amd64 3.5.2-2ubuntu0~16.04.4 [5.998 B]
Get:2 http://de.archive.ubuntu.com/ubuntu xenial/universe amd64 python3-venv amd64 3.5.1-3 [1.106 B]
Fetched 7.104 B in 0s (22,3 kB/s)
Selecting previously unselected package python3.5-venv.
(Reading database ... 466428 files and directories currently installed.)
Preparing to unpack .../python3.5-venv_3.5.2-2ubuntu0~16.04.4_amd64.deb ...
Unpacking python3.5-venv (3.5.2-2ubuntu0~16.04.4) ...
Selecting previously unselected package python3-venv.
Preparing to unpack .../python3-venv_3.5.1-3_amd64.deb ...
Unpacking python3-venv (3.5.1-3) ...
Processing triggers for man-db (2.7.5-1) ...
Setting up python3.5-venv (3.5.2-2ubuntu0~16.04.4) ...
Setting up python3-venv (3.5.1-3) ...
pooja@X1-Carbon-6:~/Documents/sva/projekten$