Re: What does XP do with lease for shutdown/restart?

Tech-Archive recommends: Repair Windows Errors & Optimize Windows Performance

In article <070m74xuen.ln2@xxxxxxxxxxxxxxxxxxxx>,
baloo@xxxxxxxxx says...

It's clear that either the computer or the router is
saving the old lease info through a power-down, and
then they just set up the same lease when powered up.

Right. DHCP clients are supposed to explicitly send the
DHCP server a DHCP RELEASE when it's not going to use
the lease any more. No version of Windows does this,
even if you explicitly release in ipcfg, ipconfig,
"repair network connection," or disabling the network
interface. Because Windows does not do this, as far as
the DHCP server is concerned, Windows doesn't release
the lease.

What I want them to do is start over with a new lease
when powered up, which is what always happened with a
direct connection to Cox without the router.

DHCP doesn't work that way. DHCP servers will always
give you the IP of your last lease, even if it's expired
or you have released it (though the latter is not
possible in Windows). DHCP servers identify your
computer by MAC address, if you want DHCP to give you a
different IP, you need to either specifically configure
the DHCP server to give you the specific IP assignment
you want. If you can't/won't/don't have access to do
that need to change network cards entirely.

Well, it's not the assigned IP address that's the problem,
it's the lease term that I want to start over. And that's
only because for some reason it isn't renewing mid-term, and
my internet conection gets shut down when it finally
expires. If it would start a new lease term on reboot, as a
practical matter it wouldn't be a problem because I shut
down overnight.

And by the way, I tried doing "ipconfig /release" and
rebooting, and it DID start the term over on reboot. Maybe
my router's DHCP server is just goofy enough to recognize
what happening. Or, maybe the problem all along was that it
was the computer, not the router, that was remembering the
original term and asking for it to be reinstated.

So it appears I do need to figure out how to establish a
shutdown script or batch file, both for MCE and Home.

If I fix the connections to specific local IP numbers,
so that DHCP is no longer involved, do leases just go
away?

No. You should never, ever statically assign yourself
when you're using a DHCP assigned network. Sooner or
later, this *will* cause an IP conflict, and you will be
the cause.

It's only the LAN side that would have fixed IPs. I don't
see how that would cause a conflict. Each computer has its
MAC, and would be assigned IPs accordingly at the router.
On the WAN side the router would continue to use DHCP with
the ISP.


.

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