When I log into my Ubuntu terminal tty1, I get a message
failed to connect to http://changelogs.ubuntu.com/meta-release
I try various things, then I get an error message telling me
could not resolve us.archive.ubuntu.com
ping us.archive.ubuntu.com -c 4:
ping: archive.ubuntu.com: name or service not known
And the same message for
sudo apt-get update.
I did not set any proxy; I left it blank during install.
My internet connectivity is apparently disabled and I could not configure it.
I tried rebooting but nothing changed.