Following are the results of running those commands :
ankit@ubuntu:~$ sudo ifconfig
[sudo] password for ankit:
eth0 Link encap:Ethernet HWaddr 00:0c:29:3b:75:fe
inet6 addr: fe80::20c:29ff:fe3b:75fe/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:208 errors:0 dropped:0 overruns:0 frame:0
TX packets:13 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:22722 (22.7 KB) TX bytes:2094 (2.0 KB)
Interrupt:18 Base address:0x2000
eth1 Link encap:Ethernet HWaddr 00:0c:29:3b:75:08
inet6 addr: fe80::20c:29ff:fe3b:7508/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:200 errors:0 dropped:0 overruns:0 frame:0
TX packets:15 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:21582 (21.5 KB) TX bytes:2778 (2.7 KB)
Interrupt:17 Base address:0x2080
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:14 errors:0 dropped:0 overruns:0 frame:0
TX packets:14 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:976 (976.0 B) TX bytes:976 (976.0 B)
ankit@ubuntu:~$ nslookup
www.linuxquestions.org
;; connection timed out; no servers could be reached
ankit@ubuntu:~$ dig
www.linuxquestions.org
; <<>> DiG 9.7.0-P1 <<>>
www.linuxquestions.org
;; global options: +cmd
;; connection timed out; no servers could be reached