Hi
Have a puzzling network connection issue. Running Ubuntu-mate 16.04
Most websites are taking forever to load including but not limited to my webmail server. And then when I try and log in get an error saying "Couldn't connect to server"

Fine. So first thought is it MUST be the actual email server or my network. But I connect to the exact same domain on the exact same network from a 2nd PC(Windows 10 laptop) and there are NO issues, the site loads in no time and I can log in without issue.
I tried rebooting and also restarting my router, no difference.

So this must be some network related setting specific to my Ubuntu machine.
Possibly DNS related?
How can I troubleshoot this further?

Could be browser related, try restarting with addons disabled.
You said "Most websites", so there are other excepts behaving the same?

I use
8.8.8.8
4.2.2.2
for /etc/resolv.conf (or other forward points) where ever I have a choice on my network.

Windows on same network suggests cache/profile/addon.

Test against http://downforeveryoneorjustme.com/# (accepts IPs)
You running a dns daemon?

Try and let us know.

No not browser related as Chromium has same issue.

Google.ca en.wikipaedia.org load instantly! Most others do not!

Seems random. apple.com instant load, apple.ca just see "Connecting"

Other websites, including downforeveryoneorisitjustme I just see a spinning icon and "connecting", after about 30 sec to a minute the page finally loads!

Recently did a sudo apt-get update sudo apt-get upgrade

Possibly something went awry with my networking..?