We have a development webserver (ubuntu) with some websites running on it. Most of the time this works fine but since some time when we are developing we get a "cannot connect" error when loading a webpage, nothing special, even on a simple html page. A page that a minute ago worked fine, this lasts for a couple of minutes and after which it starts working again.
So for a couple of minutes we cannot connect to our server with http request, ssh for example works fine. We monitored the server load but this remains 0.03 the entire time.
We thought the problem would be Apache or Mysql but even after restarting them both the server stayed unreachable.
Update: When the server is unreachable via the domain name, it still works when we use the ip adres of the server. So I don't think the server itself is the problem, but something in the dns our on the router.
Anyone an idea what the problem could be?