> set type=ns
> yahoo.com.tw
Server: dns.seed.net.tw\
Address: 139.175.55.244#53

Non-authoritative answer:
yahoo.com.tw nameserver = ns2.yahoo.com.
yahoo.com.tw nameserver = ns1.yahoo.com.
yahoo.com.tw nameserver = ns4.yahoo.com.
yahoo.com.tw nameserver = ns3.yahoo.com.
yahoo.com.tw nameserver = ns5.yahoo.com.

Authoritative answers can be found from:
> server ns2.yahoo.com
Default server: ns2.yahoo.com
Address: 68.142.255.16#53
> set type=a
> yahoo.com.tw
;; connection timed out; no servers could be reached
> tw.yahoo.com
;; connection timed out; no servers could be reached
> server 127.0.0.1
Default server: 127.0.0.1
Address: 127.0.0.1#53
> www.yahoo.com.tw
;; connection timed out; no servers could be reached
> server ns4.yahoo.com
Default server: ns4.yahoo.com
Address: 98.138.11.157#53
> www.yahoo.com.tw
;; connection timed out; no servers could be reached
> server ns3.yahoo.com
Default server: ns3.yahoo.com
Address: 203.84.221.53#53
> www.yahoo.com.tw
Server: ns3.yahoo.com
Address: 203.84.221.53#53

www.yahoo.com.tw canonical name = rc.yahoo.com.
rc.yahoo.com canonical name = src.g03.yahoodns.net.

怪了,我這邊一點改善都沒有,一直問到ns3 才有回應 ....