[root@localhost ~]# ifconfig
eth0      Link encap:Ethernet  HWaddr 00:12:17:54:40:DD
          inet6 addr: fe80::212:17ff:fe54:40dd/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:20801 errors:0 dropped:0 overruns:0 frame:0
          TX packets:9 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:1389102 (1.3 MiB)  TX bytes:1746 (1.7 KiB)
          Interrupt:10 Base address:0x4c00

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:1657 errors:0 dropped:0 overruns:0 frame:0
          TX packets:1657 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:1516078 (1.4 MiB)  TX bytes:1516078 (1.4 MiB)

[root@localhost ~]# dhclient eth0
Internet Systems Consortium DHCP Client V3.0.1
Copyright 2004 Internet Systems Consortium.
All rights reserved.
For info, please visit http://www.isc.org/products/DHCP

Listening on LPF/eth0/00:12:17:54:40:dd
Sending on   LPF/eth0/00:12:17:54:40:dd
Sending on   Socket/fallback
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 7
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 13
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 14
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 11
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 11
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 5
No DHCPOFFERS received.
No working leases in persistent database - sleeping.
[root@localhost ~]#