Sorry, we're back.
It sorta was a DNS issue. There was an emergency router replacement at the datacenter, and it affected two of our servers, one of which houses the nameservers. So some servers were accessable via IP, the others were not accessable at all.
But they informed me that everything should be all set. Normally hardware maintinence like this would be announced and scheduled for early morning hours, but they had no chance in this instance.
So you can breathe easy.. just a hardware glitch, nothing major. Just a bad coincidence