manually forcing a IP renewal
Brian McKee
brian.mckee at gmail.com
Mon Nov 26 21:28:40 UTC 2007
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
On 26-Nov-07, at 4:06 PM, Derek Broughton wrote:
> Brian McKee wrote:
>>> When he removes this ubuntu computer and connect his Windows
>>> computer,
>>> the windows computers gets a ip right away.
>>
>> I believe Windows does not release IP addresses by default.
>> Try ipconfig /release on the Windows box before you shut it down,
>> then start up the Linux box and see if it gets issued something.
>
> It's worth a try, but I don't believe it can make a difference. As
> far as
> the DHCP server is concerned, your computer has no OS. All it sees
> is a
> MAC address. Since that is the same when you're running in Ubuntu or
> Windows, you should (and I always do) get the same IP address from the
> server
Well, it's been a bit since I was poking at this, so I may be
remembering this incorrectly, but - the dhcp server in the cable
modem only has a limited number of addresses it will assign (two for
my local cable company) and if Windows doesn't release it's lease,
then there aren't any more available until one times out, or the
modem is power cycled long enough for it to erase it's existing leases.
When he says the Windows computer gets an ip right away, in fact it's
just using the one it had when it shut down.
You are right that the modem doesn't care what's plugged into it - if
he tried a new Windows computer it wouldn't work either.
Some cable companies preprogram an allowed MAC address into their
modems and ask you for that address when you set up your account with
them. That's why a lot of home routers have a option to assign MAC
numbers to their WAN port. If it was something like that he could
flop ethernet cards between the Windows box and the linux box just to
prove it, but that doesn't quite fit the symptoms he reports.
Hope that makes sense,
Brian
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.7 (Darwin)
Comment: Verify this email or encrypt your email for free - see gnupg.org
iD8DBQFHSzqIGnOmb9xIQHQRAk5SAJ9Px3c4goP4FAztGyxibCLGA4uVYACfcaML
2XYSDF3xwYqW1rVm50KYnPU=
=/ICk
-----END PGP SIGNATURE-----
More information about the ubuntu-users
mailing list