What tools should I use for DNS diagnostic?

You can use the dig utility from dns-utils (packaged with bind usually), and use the +trace option.

Output

Your dns servers seem to be "dns200.anycast.me" and "ns200.anycast.me". Is this correct? They returned no response, so start looking there. If you've changed DNS server addresses, the change can take some time to propagate (in my experience, up to 24hours).


Kudos for not obfuscating your domain name! In addition to the reply from @Mulaz, you can use the public dnscheck service from the Swedish registry. It shows the same as mulaz says - your domain is supposed to be handled by anycast.me, but their servers don't have any information about it. So you need to contact your DNS provider and ask what's going on.


nslookup is a basic but useful tool. ping and traceroute will tell you if the name resolved, but nslookup will give you the name associated with an IP, vice versa, and also the server that returned that answer. A sample output is below:

C:\Users\me\Desktop>nslookup google.com
Server:  safewall.dyndns.org
Address:  192.168.1.1

Non-authoritative answer:
Name:    google.com
Addresses:  2607:f8b0:4009:806::100e
          74.125.225.65
          74.125.225.68
          74.125.225.67
          74.125.225.66
          74.125.225.73
          74.125.225.78
          74.125.225.72
          74.125.225.71
          74.125.225.70
          74.125.225.69
          74.125.225.64


C:\Users\me\Desktop>nslookup 74.125.225.73
Server:  safewall.dyndns.org
Address:  192.168.1.1

Name:    ord08s07-in-f9.1e100.net
Address:  74.125.225.73