I'm not sure where to put this topic, I think it is actually a DNS problem, but I cannot find DNS forum, so I apologize if it's in the wrong place.
I am on unmanaged dedicated server, everything was running smoothly for 3 years, until recently the hard drive crashed and my webhost had to put a new HD and reload OS.
Since then, all my sites have a problem. The visitors (including myself) first see "Cannot find server" message, and need to hit reload browser button 2-3 times, only than the pages come up. And sometimes, on certain providers, never come up.
I know it's not browser related, as it's the same in 3 browsers, and it only started after OS reload and only happens on my sites. I know it's something in DNS settings of server, but have no idea where exactly to look and what to change, I'm afraid to mess with DNS.
Maybe somebody can help and point me into the right direction? I use WHM panel.