/etc/init.d/networking restart
 * Reconfiguring network interfaces...                                                                                                         RTNETLINK answers: No such process
There is already a pid file /var/run/dhclient.wlan0.pid with pid 2537
killed old client process, removed PID file
Internet Systems Consortium DHCP Client V3.1.1
Copyright 2004-2008 Internet Systems Consortium.
All rights reserved.
For info, please visit http://www.isc.org/sw/dhcp/

wifi0: unknown hardware address type 801
wifi0: unknown hardware address type 801
Listening on LPF/wlan0/00:1b:9e:28:ea:20
Sending on   LPF/wlan0/00:1b:9e:28:ea:20
Sending on   Socket/fallback
DHCPRELEASE on wlan0 to 192.168.3.254 port 67
send_packet: Network is unreachable
send_packet: please consult README file regarding broadcast address.
Internet Systems Consortium DHCP Client V3.1.1
Copyright 2004-2008 Internet Systems Consortium.
All rights reserved.
For info, please visit http://www.isc.org/sw/dhcp/

wifi0: unknown hardware address type 801
SIOCSIFADDR: No such device
eth0: ERROR while getting interface flags: No such device
eth0: ERROR while getting interface flags: No such device
wifi0: unknown hardware address type 801
Bind socket to interface: No such device
Failed to bring up eth0.
Internet Systems Consortium DHCP Client V3.1.1
Copyright 2004-2008 Internet Systems Consortium.
All rights reserved.
For info, please visit http://www.isc.org/sw/dhcp/

wifi0: unknown hardware address type 801
wifi0: unknown hardware address type 801
Listening on LPF/wlan0/00:1b:9e:28:ea:20
Sending on   LPF/wlan0/00:1b:9e:28:ea:20
Sending on   Socket/fallback
DHCPDISCOVER on wlan0 to 255.255.255.255 port 67 interval 3
DHCPDISCOVER on wlan0 to 255.255.255.255 port 67 interval 3
DHCPDISCOVER on wlan0 to 255.255.255.255 port 67 interval 7
DHCPDISCOVER on wlan0 to 255.255.255.255 port 67 interval 7
DHCPDISCOVER on wlan0 to 255.255.255.255 port 67 interval 8
DHCPDISCOVER on wlan0 to 255.255.255.255 port 67 interval 14
DHCPDISCOVER on wlan0 to 255.255.255.255 port 67 interval 8
DHCPDISCOVER on wlan0 to 255.255.255.255 port 67 interval 11
No DHCPOFFERS received.
No working leases in persistent database - sleeping.