Domain Name System
The Domain Name System (DNS) is a distributed, hierarchical database for converting DNS names into IP addresses. The key-value store can be used for more than just IP address information. The DNS protocol runs in two different modes:
- Recursive with caching mode.
- Authoritative mode.
When a network node makes a DNS query, it most often makes that query against a recursive, caching server. That recursive, caching server will then make a recursive query through the DNS database, until it comes to an authoritative server. The authoritative server will then send the answer for the query.
The DNS database consists of a tree-like, key-value store. The database is broken into tree nodes called domains. These domains are managed as part of a zone. Zones are the area of the namespace managed by authoritative server(s).
Tools
Servers:
- BIND
Clients:
dighostnslookupnsupdate