How aliases are used in DNS? Explain.

CNAME entries are analogous to a symbolic link in a file system- the entry gives an alias for other DNS entry. Corporation of expertsmind has two computers named as hobbes.expertsmind.com and calvin. expertsmind.com. Assume that expertsmind choose to run a web server and needs to follow the convention of using the name www for the computer which runs the organization's Web server. Though, the organizations could select to rename one of their computers, a much easier solution exists: the organization can create a CNAME entry for www.expertsmind.com which points to hobbes. At any time a resolver sends a request for www. expertsmind.com , the server returns the address of computer hobbes.

The utilization of aliases is particularly convenient since it permits an organization to modify the computer used for a special service without changing the addresses or names of the computers. For illustration expertsmind Corporation can move its web service from computer hobbes to computer calvin through moving the server and changing the CNAME record into the DNS server- the two computers retain their original IP addresses and names.