"I thought it was a DNS server problem (that is what it looks like), but i can't even access a website with the IP address."
You can double check whether or not it is a DNS problem by looking at /etc/resolve.conf. You should have something like this in /etc/resolve.conf:
Where the search field is the name of your DNS in letters and the nameserver field is the name of your DNS in numbers.
Be prepared. Create a LifeBoat CD.