Problem with connecting to server, it worked before

I have started playing on this server around a month ago, everything went smoothly, great server , great community.
But around a week ago when I tried to connect I got the ominous "Unable to connect to Battle.net" message. Nothing has changed in my configs on pc nor on the router. A few day later my friend told me he is also experiencing this problem but he could still connect sometimes. We are both playing from Hungary.

The BnetLog file has this:
5/26 16:20:07.140 Connecting to Battle.net...
5/26 16:20:07.158 querying gateway d2.europebattle.net
5/26 16:20:07.208 searching for the fastest server
5/26 16:20:33.206 no servers found

On the other hand I can ping the address from my pc.

I tried to reinstall , it didn't help...

Does anyone has any idea what could cause this?