Question 1) Test Yourself on CompTIA i-Net+.

Objective : Network
SubObjective : Understand and be able to Describe the Use of Internet Domain Names and DNS
Single Answer Multiple Choice

DNS uses a lookup table to resolve names. Which record type in the DNS table is used for the assignment of multiple, fully qualified domain names to one IP address?

A. A
B. MX
C. PTR
D. CNAME

Answer:
D. CNAME

Tutorial:
An IP address can be assigned to more than one fully qualified domain name. The DNS lookup table must contain the multiple names for the IP address. The record in the DNS table that denotes an IP address assigned multiple, fully qualified domain names is CNAME, which stands for canonical name. An example of the CNAME record is:

www.comptia.org IN A 207.254.119.234
ftp.comptia.org IN CNAME www.comptia.org

A is an address record. The A record is used to directly map the record’s host name to its IP address.

MX is a mail exchange record. The MX record is used to identify the mail exchanger for a host.

PTR is a pointer record. The PTR record is used to directly map the record’s IP address to its hostname.

These questions are derived from the Self Test Software Practice Test for CompTIA Exam #IK0-002: i-Net+.