DNS debugging

 Doing some digging about why a specific DNS wasn't propagating properly everywhere, I found out that it was related to a wrong DNSSEC declaration.

• Tool to check if the DNS record is properly propagated https://www.whatsmydns.net
• Debug DNS settings & DNSSEC settings
• https://dnsviz.net
• https://www.zonemaster.net/ 

a bit more details about DNSSEC 

https://blog.ovhcloud.com/an-introduction-to-dnssec/

DNS DNSKEY and DS records "The DNSKEY and DS records are used by DNSSEC resolvers to verify the authenticity of DNS records."

https://www.cloudflare.com/learning/dns/dns-records/dnskey-ds-records/

some debuging steps

https://serverfault.com/questions/1018543/dns-not-resolving-in-all-locations-after-a-week