Question about DNS and Registrars

[Jailer]

I've got a question for those of you that have some webs hosting/sysadmin experience. I recently purchased a domain name through namecheap for a small private discussion forum that I host for a friend from my home. Twice now in the last couple months the name won't resolve. But the weird part is the site will resolve for some but not for others including myself. I can of course connect locally no problem but the web address will return a DNS error.

Keep in mind the site was working perfectly for over a year using a free subdomain from freedsns and never had any dns issues. The problem only started appearing after the domain purchase. Oddly enough after I got done chatting with tech support tonight and having them tell me it was all a problem on my end the site came back up within a a couple minutes.

How can I prove this is not a problem on my end? Or if the problem is on my end how can I trouble shoot it to find out?

 

[jgreco]

Suggest heading over to http://dns.measurement-factory.com/tools/third-party-validation-tools/

Some of us have been running name service at scale for decades, but in the end there's no way I'm going to be able to impart sufficient knowledge on you to do the checking by hand that many tools will do automatically these days. Get familiar with several of the tools listed above, and then compare results when things are "broke."

 

[Jailer]

Thanks for those links.

Most everything I checked when it was "broke" returned the same thing; DNS could not be resolved which is why I am suspect of the namecheap DNS servers. If it falters again I'll check some of those links and see what they can come up with.

 

[jgreco]

"DNS could not be resolved" is a hideously vague condemnation. The DNS is a tree and you should be able to step through and validate correct operation at each level, and each server at that level.