interfaces:

auto lo
iface lo inet loopback
auto eth0
iface eth0 inet dhcp

ifconfig:
eth0	Link encap:Ethernet	HWaddr 08:00:27:82:b1:d5
	inet6 addr: fe80::a00:fe82:b1d5/64 Scope:Link
	UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
	RX packets:0 errors:0 dropped:0 overruns:0 frame:0
	TX packets:33 errors:0 dropped:0 overruns:0 carrier:0
	collisions:0 txqueuelen:1000
	RX bytes:0 (0.0 B)	TX bytes:9198 (9.1 KB)
	Interrupt:10 Base address:0xd020

lo	Link encap:Local Loopback
	inet addr:120.0.0.1	Mask: 255.0.0.0
	inet6 addr: ::1/128 Scope:Host
	UP LOOPBACK RUNNING MTU:65536 Metric:1
	RX packets:32 errors:0 dropped:0 overruns:0 frame:0
	TX packets:32 errors:0 dropped:0 overruns:0 carrier:0
	collisions:0 txqueuelen:0
	RX bytes:2368 (2.3 KB)	TX bytes:2368 (2.3 KB)