The Domain Name System or DNS is defined as a hierarchical naming system for computers, services, or any resource connected to the Internet or a private network. It connects different bits of information with domain names assigned to each of the participants. Additionally, and perhaps its most important use, it translates domain names that are meaningful to humans into the numerical or binary identifiers associated with networking equipment for the intended purpose of locating and addressing these devices globally. A Domain Name System is in some way much like a “phone book” for the Internet by translating human-friendly computer hostnames into actual IP addresses. For example, www.example.com would translate to numerals within this formation xxx.xxx.xxx.xxx.
The Domain Name System allocates the responsibility of assigning domain names and mapping those names to unique IP addresses by specifying authoritative name servers for each domain. Authoritative name servers are allocated to be responsible for their specific domains, and additionally they can assign other authoritative name servers for their own sub-domains. This mechanism enhances the reliability of the DNS making it fault tolerant which subsequently helps to avoid the need for a single central register to be continually consulted and updated.
Generally, the Domain Name System is also used to store other types of information, for example, the list of mail servers that accept email for a given Internet domain. By enabling a worldwide, distributed keyword-based redirection service, the Domain Name System is a vital constituent of the Internet’s overall performance and functionality.
There are times where it might be necessary to flush dns to get a new name resolution. Additionally you may decide to flush dns cache when you cannot access a newly registered domain name. You can easily flush your dns cache at any point to get a new entry. It is a fairly easy process that takes very little time. Below, there are instructions to flush DNS using any of the three major Operating Systems: Linux, Windows or MAC is explained.
Flush DNS cache if using a Microsoft Windows Operating System (Win XP, Win ME, Win 2000)
- Go to Start
- Then go to Run
- Enter cmd
- Once in command prompt, type ipconfig /flushdns
- The operation should now be complete.
To flush the DNS cache in Linux, restart the nscd daemon
- To restart the nscd daemon, Open the terminal and then type /etc/rc.d/init.d/nscd restart
- Once you run this command your linux DNS cache will flush.
How to flush the DNS cache in OS X Leopard
- Type lookupd -flushcache in your terminal to flush the DNS resolver cache.
- ex: bash-2.05a$ lookupd -flushcache
- Once you run the command your DNS cache (in Mac OS X) will flush.
Flush the DNS cache in Mac OS X
- Type dscacheutil -flushcache in your terminal to flush the DNS resolver cache.
- ex: bash-2.05a$ dscacheutil -flushcache
- Once you run the command your DNS cache (in Mac OS X Leopard) will flush.