Serious Wi-Fi network issue on Ubuntu 17.04

Question

I have a serious issue after upgrading from Ubuntu 16.10 to 17.04.

My machine is connected to wifi and IP address is obtained. But there is no internet connection.

Everything was working fine before the upgrade.

In /var/log/syslog I can see many DNSSEC validation failed messages.

I tried this, but did NOT help:

[device]
wifi.scan-rand-mac-address=no

Then restart network-manager

Answer 1

As written here, create the file /etc/systemd/resolved.conf.d/no-dnssec.conf with the following content:

[Resolve]
DNSSEC=no

And restart. I tried the scan-rand-mac-address thing and adding 8.8.8.8 as DNS, but that was the only thing that worked for me.

Answer 2

Here is a link of the bug.

And here is what you should try:

Open a terminal and type or paste this and run it:

sudo -H gedit /etc/NetworkManager/NetworkManager.conf

Then edit the file and add these lines to the bottom of the file:

[device]
wifi.scan-rand-mac-address=no

Save the file and run this command in a terminal:

sudo service network-manager restart

EDIT: Sorry, just read your edit to your question.

Try this line of code(it fixed my internet in 16.10 and 17.04:

sudo killall dnsmasq