Domains

Domain Names & Levels

• Root: .

• Top Level Domain (TLD)

• E.g., .com, .net, .gov

• Second Level Domain (SLD)

• Also known as apex domain
• Configured with A, ALIAS or ANAME records

• E.g., amazon.com, google.com

• Subdomain

• Configured with CNMAE record
• E.g, api.amazon.com.

• Resolving steps
• Hit the local dns server
• Hit the root dns server
• Hit the .com dns server
• Hit the google dns server: serve you with the IP of the apps subdomain

Fully Qualified Domain Name (FQDN)

• The fully qualified domain name (FQDN), such as www.example.com
• You can use wildcards to match all the subdomains in a domain. E.g., *.example.com