why nslookup kent.edu and www.kent.edu output different result?

Question

nslookup kent.edu
* Can't find server name for address 221.176.88.95: Non-existent domain
* Can't find server name for address 211.138.164.6: Non-existent domain
*** Default servers are not available
Server: UnKnown
Address: 221.176.88.95

Name: kent.edu

nslookup www.kent.edu
* Can't find server name for address 221.176.88.95: Non-existent domain
* Can't find server name for address 211.138.164.6: Non-existent domain
*** Default servers are not available
Server: UnKnown
Address: 221.176.88.95

Non-authoritative answer:
Name: www-new.kent.edu
Address: 131.123.246.53
Aliases: www.kent.edu

why nslookup kent.edu and www.kent.edu output different result?

Answer 1

This would be occurring because there is no "A" record set up for kent.edu but there is one set up for www.kent.edu. The chain of logic I used (under Linux) to determine this:

dig kent.edu ns

; <<>> DiG 9.8.1-P1 <<>> kent.edu ns ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 55191 ;; flags: qr rd ra; QUERY: 1, ANSWER: 3, AUTHORITY: 0, ADDITIONAL: 3

;; QUESTION SECTION: ;kent.edu. IN NS

;; ANSWER SECTION: kent.edu. 223 IN NS dhcp.net.kent.edu. kent.edu. 223 IN NS ns.net.kent.edu. kent.edu. 223 IN NS adns03.net.kent.edu.

;; ADDITIONAL SECTION: ns.net.kent.edu. 231 IN A 131.123.1.1 dhcp.net.kent.edu. 231 IN A 131.123.252.2 adns03.net.kent.edu. 231 IN A 128.146.94.250

;; Query time: 1 msec ;; SERVER: 10.0.3.254#53(10.0.3.254) ;; WHEN: Wed Jan 1 17:00:57 2014 ;; MSG SIZE rcvd: 135

dig @131.123.1.1 kent.edu a

; <<>> DiG 9.8.1-P1 <<>> @131.123.1.1 kent.edu a ; (1 server found) ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 22704 ;; flags: qr aa rd; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 0 ;; WARNING: recursion requested but not available

;; QUESTION SECTION: ;kent.edu. IN A

;; AUTHORITY SECTION: kent.edu. 300 IN SOA ns.net.kent.edu. postmaster.net.kent.edu. 23142476 1200 180 2419200 300

;; Query time: 265 msec ;; SERVER: 131.123.1.1#53(131.123.1.1) ;; WHEN: Wed Jan 1 17:01:56 2014 ;; MSG SIZE rcvd: 80

dig @131.123.1.1 www.kent.edu a

; <<>> DiG 9.8.1-P1 <<>> @131.123.1.1 www.kent.edu a ; (1 server found) ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 9928 ;; flags: qr aa rd; QUERY: 1, ANSWER: 2, AUTHORITY: 3, ADDITIONAL: 3 ;; WARNING: recursion requested but not available

;; QUESTION SECTION: ;www.kent.edu.         IN  A

;; ANSWER SECTION: www.kent.edu.        300 IN  CNAME   www-new.kent.edu. www-new.kent.edu. 300 IN  A   131.123.246.53

;; AUTHORITY SECTION: kent.edu.     300 IN  NS  adns03.net.kent.edu. kent.edu.      300 IN  NS  ns.net.kent.edu. kent.edu.      300 IN  NS  dhcp.net.kent.edu.

;; ADDITIONAL SECTION: ns.net.kent.edu. 300 IN  A   131.123.1.1 dhcp.net.kent.edu.  300 IN  A   131.123.252.2 adns03.net.kent.edu.  300 IN  A   128.146.94.250

;; Query time: 274 msec ;; SERVER: 131.123.1.1#53(131.123.1.1) ;; WHEN: Wed Jan  1 17:02:20 2014 ;; MSG SIZE  rcvd: 177

Answer 2

Or, more fundamentally and unstated in davidgo's answer: Because kent.edu and www.kent.edu are two different domain names. Different domain names, that whoever administers them has assigned different DNS resource records to. A human being has decided that what you saw is what the DNS data are going to be (almost certainly because it's not permitted to have an alias at a delegation point) for those two different domain names. It's that simple.