My ISP currently has a problem with a fiber link that affects 25% of their customers – including me. This means that the link to 184.108.40.206 is currently unavailable. Domains resolving to 220.127.116.11 (the DSL link to the server) can still be used (e.g. by visiting mirror.mertner.com instead of www.mertner.com).
The problem should be solved within an hour or two.