Root Server
They are the top level of the DNS Hierarchy
There are 13 set of Root Servers strategy placed around the world
Operated by large organizations and universities like NASA, USC, ICANN and DoD
They are named using letters A through M (letter.root-servers.net)
Root Server Info Page can be accessed at letter.root-servers.org
The G Root Server Info Page: https://disa.mil/g-root
Info about all root servers can be found at www.root-servers.org
Top Level Domain (TLD) Server
There are different TLD for the different extensions
.com TLD Server stores information about all sites ending in .com
Authoritative Name Server details entered in the Domain Registrars website
Registrar tells TLD managing authority to update its records with the Authoritative Name Server details provided by user
Authoritative Name Server
Scans Zone files to find the Domain name to IP Address mapping
These servers are run we organizations providing web hosting services
Commands
| Description | Command |
|---|---|
| Get Root Nameservers | dig NS . |
| Get TLD Nameservers | dig NS com @a.root-servers.net |
| Get Authoritative Nameservers | dig NS google.com @a.gtld-servers.net |
| Get Domain IP Address | dig google.com @ns1.google.com |