Shekhar,
up in ifconfig, ping <domain> (say, ping google.com) gives me "Host not Found" messege when I ping. Needless to say that my browser gives me the same error when I try to access a website. The funny thing is that previously resolved DNS (such as an on-going download) continues, but new queries do not resolve after a minute or so of the network start. When I restart the network using /etc/init.d/network restart, the same story repeats - DNS resolving fine for some time and then it doesn't work. I even tried using latest FC3 update of rp-pppoe, but things look the same.
This is 100% problem of DNS Servers of your provider. Try this, once your connection gets establilshed in linux cat /etc/resolv.conf (does it have any entry like nameserver so.me.ip.add ) If this file doesnt have any such line, then you gotta add one: nameserver 202.9.136.6 (google for public name servers)
Thanks & Regards, Mitul Limbani, Founder & CEO, Enterux Solutions, The Enterprise Linux Company (TM), www.enterux.com