What is authoritative and recursive DNS?

What is authoritative and recursive DNS?

Authoritative DNS servers are the authority on DNS records and store DNS record information while recursive DNS servers interact directly with the end user. The recursive DNS server reads a user’s DNS request and either uses cached data to respond or attempts to discover the answer and then respond.

What is a recursive DNS?

A recursive DNS lookup is where one DNS server communicates with several other DNS servers to hunt down an IP address and return it to the client. This is in contrast to an iterative DNS query, where the client communicates directly with each DNS server involved in the lookup.

What is authoritative server DNS?

An authoritative server is the authority for its zone. It queries and is queried by other name servers in the DNS. The data it receives in response from other name servers is cached. Authoritative servers are not authoritative for cached data. Both master and secondary name servers are authoritative for a zone.

What is DNS and types of DNS?

The three DNS server types server are the following: DNS stub resolver server. DNS recursive resolver server. DNS authoritative server.

How do I find my authoritative DNS?

To find out who is responsible for DNS hosting of a domain, you need to find the authoritative DNS servers (or Name Servers) for that domain. A list of DNS servers authoritative for the domain is shown in the Name Server (NS) record. To find this record, you can use the NSLOOKUP tool.

How do I know if my DNS is recursive?

Use dig and check the status of the RD and RA bits in the response. By default dig will send a recursive query ( RD set in the query header) unless you set the +norecurse command line flag. If the server supports recursive queries the response will have the “recursion available” RA bit set in the response headers.

What is the difference between authoritative and recursive DNS server?

An authoritative DNS server is a server that responds to DNS queries from data that has been configured by an original source such as a domain administrator or DNS methods.

Where are authoritative servers located in the DNS tree?

Authoritative name servers know where to find the level set in the hierarchy, e.g. – top-level domains. In addition, the root servers are at the top of the DNS tree. They know exactly which IP addresses of the authoritative servers are the ones that handle DNS queries for Top Level Domains (TLD) such as .com.

What’s the difference between umbrella and recursive DNS?

The Umbrella recursive DNS server first asks the root domain nameserver for the IP address of the .com TLD server, since www.google.com is within the .com TLD. The root domain nameserver responds with the address of the TLD server.

Is it safe to use recursive DNS queries?

Unfortunately, allowing recursive DNS queries on open DNS servers creates a security vulnerability, as this configuration can enable attackers to perform DNS amplification attacks and DNS cache poisoning.