Understanding Glue Records And Dedicated DNS
IBM News, Tuesday, April 16th, 2024
Domain name system (DNS) resolution is an iterative process where a recursive resolver attempts to look up a domain name using a hierarchical resolution chain.
First, the recursive resolver queries the root (.), which provides the nameservers for the top-level domain(TLD), e.g.com. Next, it queries the TLD nameservers, which provide the domain's authoritative nameservers. Finally, the recursive resolver queries those authoritative nameservers.
In many cases, we see domains delegated to nameservers inside their own domain, for instance, 'example.com.' is delegated to 'ns01.example.com.' In these cases, we need glue records at the parent nameservers, usually the domain registrar, to continue the resolution chain.