some study about DNS
A record means mapping with a ip address which binded with a host
This record is elementary configuration for http request
NS record is to let another nameserver to resolve this domain name
used for DNS resolvation only.
MX is used when a client send a email which contain
XXX@name.com, then it will search the
name.com in MX record to identify which host it resolve to .
used for mail address resolvation only.
CNAME just like a nick name for a already defined A record host.
using CNAME can enhance resolve capability while pointing to identical host.
for instance: there is a define A record
rugal.ml, and I want to make
www.rugal.ml as well as
blog.rugal.ml point to the host.
as I can achieve it by making double CNAME record which point to the
TXT have no other usefulness but to tell client about comments on of a named site