I’ve got this issue recently when installed VirtualBox on my Manjaro Linux (this distro based on Arch Linux, so the solution would work there as well).
It seems that VirtualBox, while installing its virtual network adapters, had messed up the existing physical ones. That led to the situation when, once you reboot your machine, there is no network connection to the internet.
➜ ~ ping google.com ping: google.com: Name or service not known
Well, this is pretty easy to fix.