One hardware boot-up from network,something wrong with the DHCP,as below:

DHCP client bound to address 169.254.31.206

the IP address is wrong, shall be 169.254.0.x;where could I fix the wrong ? any help!

DHCP should not serve that address. that range is only for when there is NO DHCP server in the local network responding and the client tries to find an address by itself. Is there a DHCP server under your control in this situation? That address certainly isn't "garbage" so you've not really asked anything we can answer.

Thanks Chris!

So your mean is that the node did not respond.
Seeing log as following:

BOOTP broadcast 1
DHCP client ID detected AB3 shelf
DHCP client ID detected AB3 shelf
DHCP client bound to address 169.254.31.206

So is it something wrong with AB3 shelf?

I've no idea what "ab3 shelf" is meant to mean at all. You need to describe a lot more about your environment. What problem are you even having? ou'd not properly defined anything here.

Just resolved. Thank you for your comment.

well that was productive. :S

The 169.254.0.x addresses are "autoconfiguration" addresses.

<rant>
You know, you want to connect 2 computers with a cable and the geniuses from Apple (i think) (or Microsoft? because Windows has it too) came up with this amazing idea of creating a method that will magically make the 2 computers connect or something like that (like auto discovering computers on the same LAN bla bla). Now this crap was included in Linux's desktop variants for the above mentioned reasons.

Except IT IS NOT WORKING. NEVER EVER WORKED FOR ME OR ANYBODY I KNOW!!! (i work as network admin/+tech support and i had many many situations like these)

People who just put 2 computers together just stare at them because they have absolutely no idea what they should do to actually "see" the other computer so they do what? Call someone who does and that someone will set them up with fixed IP addresses and thats that.
On the other hand this crap gets in the way because people have the feedback that their connection is "connected" but actually it isnt good for anything.
</rant>

So this marvel came to Linux under the alias of "avahi-daemon" (nice fitting name). It will do the same stuff it does under Windows - confuse users and act as a DHCP server when there isnt a real one around. Just UNINSTALL the damn thing wherever you find it (it might not be easy because the Gnome guys think of this crap as a good complement for their crap DE so they wired it deep in network-manager).