Renew ip address for DHCP client
I had a wierd situation recently, I could get the ip address, and I could set up apt.conf and proxy correctly, but I just could not connect network, I even could ping a inner desktop, so wierd. Then suddently, I found that it responses twice when ping this ip, so it is probably that the ip is used by other people stactly already, so I need to get a new automatic ip address, here is what I did:
1. release your current dhclient
sudo dhclient -r
or
sudo dhclient -r eth0
r for release.
2 obtain fresh IP
sudo dhclient
or
sudo dhclient eth0
3 show the detail information.
sudo dhclient -v -r eth0
or
sudo dhclient -v eth0
v for verbose
other option may be useful
ifdown eth0
ifup eth0
/etc/init.d/networking restart