Today I ran into problem when my girlfriend's laptop crashed. The problem was that the X server didn't start, just kept blinking for a few seconds and then one couldn't do anything except for rebooting. Yesterday we were installing VirtualBox onto that machine, but I wouldn't say that it caused the X server to crash. Anyway, when I rebooted the laptop with an installation DVD of Fedora inside, the rescue box couldn't configure network properly. The laptop has been connected to the router via cable, the router would assign it a dynamic IP address, so I couldn't understand why am getting
connect: Network is unreachable
after executing the following command
ping www.google.com
It was weird, because pinging 192.168.2.1 which is my router's IP was 100% successful. Anyway, the fix was easy, it all needed the following command
service network restart
Since then, the network was always configured properly.