Updated: February 8th, 2017
Today I was setting up a new machine (running OpenSUSE 12.1, but it's not really important), and after switching the network configuration from DHCP to static IP, lost all connectivity, in and out. /etc/init.d/network restart seemed to list the right IP, yet I was getting
"Network is unreachable"
errors while pinging. I double and triple checked all the settings – DNS and gateway were set up right. I even rebooted, but nothing worked.
Then I vaguely remembered that I ran into the same issue a few years prior and also spent hours trying to figure out what was going wrong. The solution was so incredibly simple that my geek cred should have been docked 10 points. But …