What DNS server is responsible for maintaining a particular domains resource records?
NOTE: Using software to mass-download the site degrades the server and is prohibited. Custom Search DNS Name Server Data Storage: Resource Records and Classes (Page 1 of 4) One of the most important jobs performed by name servers is the storage of name data. Since the authority for registering names is distributed across the internetwork using DNS, the database of name information is likewise distributed. An authoritative server is responsible for storing and managing all the information for the zones of authority it is assigned. Each DNS server is, in essence, a type of database server. The database contains many kinds of information about the subdomains and individual devices within the domain or zone for which the server is responsible. In DNS, the database entries that contain this name information are called resource records (RRs). A specific set of RRs is associated with each node within the zone. Binary and Text Representations of Resource RecordsThe entire point of DNS is to allow humans to work with names and computers to work with numbers, and we see this principle further reflected in the two very different representations that exist for the DNS resource records themselves:
Home - Table Of Contents - Contact Us The TCP/IP Guide (http://www.TCPIPGuide.com) � Copyright 2001-2005 Charles M. Kozierok. All Rights Reserved. Finally, we’ll give you a sneak peak into the amazing things that can be achieved by the next
generation of DNS servers. DNS is a global system for translating IP addresses to human-readable domain names. When a user tries to access a web address like “example.com”, their web browser or application performs a DNS Query against a DNS server, supplying the hostname. The DNS server takes the hostname and resolves it into a numeric IP address, which the web browser can connect to. A component called a DNS Resolver is
responsible for checking if the hostname is available in local cache, and if not, contacts a series of DNS Name Servers, until eventually it receives the IP of the service the user is trying to reach, and returns it to the browser or application. This usually takes less than a second. There are three types of queries in the DNS system: In a recursive query, a DNS client provides a hostname, and the DNS Resolver “must”
provide an answer—it responds with either a relevant resource record, or an error message if it can't be found. The resolver starts a recursive query process, starting from the DNS Root Server, until it finds the Authoritative Name Server (for more on Authoritative Name Servers see DNS Server Types below) that holds the IP address and other information for the requested hostname. In an iterative query, a DNS client provides a hostname, and the DNS Resolver returns
the best answer it can. If the DNS resolver has the relevant DNS records in its cache, it returns them. If not, it refers the DNS client to the Root Server, or another Authoritative Name Server which is nearest to the required DNS zone. The DNS client must then repeat the query directly against the DNS server it was referred to. A non-recursive query is a query in which the DNS Resolver already knows the answer. It either immediately returns a DNS record
because it already stores it in local cache, or queries a DNS Name Server which is authoritative for the record, meaning it definitely holds the correct IP for that hostname. In both cases, there is no need for additional rounds of queries (like in recursive or iterative queries). Rather, a response is immediately returned to the client. DNS Types: 3 Types of DNS ServersThe following are the most common DNS server types that are used to resolve hostnames into IP addresses. DNS ResolverA DNS resolver (recursive resolver), is designed to receive DNS queries, which include a human-readable hostname such as “www.example.com”, and is responsible for tracking the IP address for that hostname. DNS Root ServerThe root server is the first step in the journey from hostname to IP address. The DNS Root Server extracts the Top Level Domain (TLD) from the user’s query — for example, www.example.com —... provides details for the .com TLD Name Server. In turn, that server will provide details for domains with the .com DNS zone, including “example.com”. There are 13 root servers worldwide, indicated by the letters A through M, operated by organizations like the Internet Systems Consortium, Verisign, ICANN, the University of Maryland, and the U.S. Army Research Lab. Authoritative DNS ServerHigher level servers in the DNS hierarchy define which DNS server is the “authoritative” name server for a specific hostname, meaning that it holds the up-to-date information for that hostname. The Authoritative Name Server is the last stop in the name server query—it takes the hostname and returns the correct IP address to the DNS Resolver (or if it cannot find the domain, returns the message NXDOMAIN). DNS Types: 10 Top DNS Record TypesDNS servers create a DNS record to provide important information about a domain or hostname, particularly its current IP address. The most common DNS record types are:
DNS Can Do Much MoreNow that’s we’ve covered the major types of traditional DNS infrastructure, you should know that DNS can be more than just the “plumbing” of the Internet. Advanced DNS solutions can help do some amazing things, including:
These capabilities are made possible by next-generation DNS servers that are able to intelligently route and filter traffic. Learn more about NS1’s intelligent DNS platform and take DNS to the next level. What type of DNS server contains records specific to domain extensions?A TLD nameserver maintains information for all the domain names that share a common domain extension, such as .com, . net, or whatever comes after the last dot in a url. For example, a .com TLD nameserver contains information for every website that ends in '.com'.
What do you call the source responsible for maintaining a domains resource records?A resolver has direct access to at least one DNS server and can also process referrals to direct its queries to other servers when necessary. The authoritative source for a domain is the DNS server responsible for maintaining that domain's resource records.
Which device is responsible for each DNS domain?Typically, when you connect to a local network, Internet service provider (ISP) or WiFi network, the modem or router sends network configuration information to your local device, including one or more DNS servers. These are the initial DNS servers your device will use to translate host names to IP addresses.
What is a record responsible for in DNS?DNS records (aka zone files) are instructions that live in authoritative DNS servers and provide information about a domain including what IP address is associated with that domain and how to handle requests for that domain. These records consist of a series of text files written in what is known as DNS syntax.
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