DNS Question
 

Is it possible to fetch all the subdomains from a domain.tld ?

dont think so, you can however check what subdomains are on the server

http://whois.webhosting.info/127.0.0.1 (replace the IP)

http://docsrv.sco.com/NET_tcpip/dnsC.nslook.html

how effective commands like "ls-d" under nslookup, etc. are depends on
whether or not the server was configured to block zone transfers, as most
are these days for reasons of privacy/security.

:2 cents:

and here's an online zone transfer checker for those not wanting to
learn the command line.

http://www.digitalpoint.com/tools/zone-transfer/

if the server was locked-down, you'll get a "transfer failed"... otherwise, you'll get the list you want.