For a period of time, I was able to access the internet from my school network but not from my home network. I was able to ping my gateway and 8.8.8.8 but nothing else.
I am writing this down as a reminder for the next time I screw this up.
I received the following error when I ran:
sudo resolvconf -u
/etc/resolvconf/update.d/libc: Warning: /etc/resolv.conf is not a symbolic link to /run/resolvconf/resolv.conf
I fixed this symlink and then again ran sudo resolvconf -u
and everything worked again.