/etc/hosts파일입니다. 호스트 파일에 따로 ip설정을 해주어야 하는것인가요?
 # Do not remove the following line, or various programs
# that require network functionality will fail.
127.0.0.1               iloveyou.com iloveyou localhost.localdomain localhost
  실제로 해보니 다음과 같은 문제가 생기네요
[root@iloveyou mail]# mail
No mail for root
[root@iloveyou mail]# nslookup
Note:  nslookup is deprecated and may be removed from future releases.
Consider using the `dig' or `host' programs instead.  Run nslookup with
the `-sil[ent]' option to prevent this message from appearing.
> set type=mx
> mail.iloveyou.com
Server:        203.241.0.0
Address:       203.241.0.0#53
 *** Can't find mail.butiloveyou.com: No answer
>
 이 2개의 차이점이 무엇인가요?
 [root@iloveyou mail]# nslookup mail.iloveyou.com
Note:  nslookup is deprecated and may be removed from future releases.
Consider using the `dig' or `host' programs instead.  Run nslookup with
the `-sil[ent]' option to prevent this message from appearing.
Server:        203.241.0.0
Address:       203.241.0.0#53
 Name:  mail.0iloveyou.com
Address:203.241.0.0
 [root@0iloveyou mail]#