[735] in resnet
Problems with Windows 2000 DHCP server Leases.
daemon@ATHENA.MIT.EDU (Ronald R. Gilmore)
Thu Jan 31 15:10:51 2002
MIME-version: 1.0
Content-type: multipart/alternative;
boundary="----=_NextPart_000_0024_01C1AA66.2FA51A60"
Message-ID: <!~!UENERkVCMDkAAQACAAAAAAAAAAAAAAAAABgAAAAAAAAA+8zCUVvookerYEtdM7GZe8KAAAAQAAAAfPRmMAwEJ0izSnGgDjpoegEAAAAA@oneonta.edu>
Date: Thu, 31 Jan 2002 14:47:20 -0500
Reply-To: gilmorrr@snyoneva.cc.oneonta.edu
From: "Ronald R. Gilmore" <gilmorrr@snyoneva.cc.oneonta.edu>
To: RESNET-L@listserv.nd.edu
This is a multi-part message in MIME format.
------=_NextPart_000_0024_01C1AA66.2FA51A60
Content-Type: text/plain;
charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable
At Oneonta State we have started the migration into the Microsoft 2000
domain world. Our first phase of this project was to upgrade our
existing NT4 - DHCP/WINS and LINUX based DNS to a Windows 2000 network
structure. We have hit a few snags with the 2000 DHCP server, and =
that=92s
why I=92m here. Here=92s what we had and what we moved to. In our old
Network environment we had 16 different subnets on 16 VLANs, using a
Linux server(s) for our DNS and an NT 4 server our DHCP/WINS using VLAN
Tagging. We had a few DUP IP=92s back then but most we could track down =
to
a malfunctioning DHCP stack or where a static IP Address was
implemented. But for the most part no problems with this design.
Everything else worked like it should. =20
=20
After moving the NT4 Lease database to 2000=92s world we have had many =
IP
Conflicts. When they first started happening it seemed like it was
somewhat random as to what was going on, but after a few weeks of
tracking down the problem we have found what seems to be causing the
problem. The NT 4, 2000, and XP machines appear not to have the problem
but Mac=92s (by product of the win9x machines we believe), 95, 98 and =
98se
in particular are seeing the problem. =20
=20
When a 9x machine gets a DHCP lease from the server for the first time
both leases are in sync with the 2000 DHCP server. We did a manual
release/renew on the 9x machine and the time stayed in sync with the
DHCP server. Then we rebooted the 9x machine and noticed that the time
became out of sync with the server. So we put a sniffer on the 9x
machine and saw the machine issue a DHCP renew at boot that was a
broadcast style, but with no response from the server. The NT/XP based
machines do a directed broadcast for their renewal of the lease upon
boot. We then looked at the server and the leases were even more out of
sync. All the while on the client 9 x machines it kept reporting that it
had renewed its lease and put the time at which it had attempted to
renew in the leases field. The next step was to reboot the machine
without a network cable attached. The same thing happened a lease was
renewed and no server was contacted. I tried this with a 2000 and XP
machine and upon boot the IP protocol doesn=92t come up until you have a
Link State on the network card. After plugging it in to the wall the
adaptor got a lease and it was in sync with the DHCP server. What this
causes is that the more times the 9x machine reboots, or even worse are
overnight powered off, machines become vastly out of sync with the DHCP
server. After 7 days, which is our lease time here, the DHCP server
then removes the lease for the 9x machine and then assigns it to another
client. The 9x machine still thinks it has more time on its lease and
thus keeps the IP.=20
=20
We have tired the DHCP release on shutdown hack but it has a very nasty
side affect with the 2000 DHCP server. When the user powers the machine
on yes their IP is released but the machine still doesn=92t do a proper
renew upon boot, and the user is forced to do a manual renew, a real
problem here! Does anyone know of a fix for the 9x client, or is an
upgrade to the OS our only solution?
=20
We also have tried to use conflict detection on the DHCP server but this
doesn=92t work when the client is powered off over night.
=20
Just to clarify my mind this is how DHCP on a 9x client
SHOULD work. New computer on network and no previous leases in its DHCP
stack. Upon boot it gets a new address from the DHCP server and its
lease time. (Given in an offset from current time on each machine.) The
9x machine is rebooted and it SHOULD keep the same lease time in its
DHCP information until it reaches the =BD way point and then attempts a
lease renewal. At this time it does a directed DHCP renew to the server
listed in its DHCP information and thus extends its lease. Also when a
9x machine is booted without a network cable the DHCP stack should come
up with no lease or a Microsoft Automatic Private IP Addresses i.e. a
169.x.x.x number.
=20
=20
=20
=20
------=_NextPart_000_0024_01C1AA66.2FA51A60
Content-Type: text/html;
charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable
<html>
<head>
<META HTTP-EQUIV=3D"Content-Type" CONTENT=3D"text/html; =
charset=3Diso-8859-1">
<meta name=3DGenerator content=3D"Microsoft Word 10 (filtered)">
<style>
<!--
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0in;
margin-bottom:.0001pt;
font-size:12.0pt;
font-family:"Times New Roman";}
a:link, span.MsoHyperlink
{color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{color:purple;
text-decoration:underline;}
span.EmailStyle17
{font-family:Arial;
color:windowtext;}
@page Section1
{size:8.5in 11.0in;
margin:1.0in 1.25in 1.0in 1.25in;}
div.Section1
{page:Section1;}
-->
</style>
</head>
<body lang=3DEN-US link=3Dblue vlink=3Dpurple>
<div class=3DSection1>
<p class=3DMsoNormal style=3D'text-indent:.5in'><font size=3D2 =
face=3DArial><span
style=3D'font-size:10.0pt;font-family:Arial'>At Oneonta State we have =
started the
migration into the Microsoft 2000 domain world. Our first phase of this =
project
was to upgrade our existing NT4 - DHCP/WINS and LINUX based DNS to a =
Windows
2000 network structure. We have hit a few snags with the 2000 DHCP =
server, and
that’s why I’m here. Here’s what we had and what we =
moved to.
In our old Network environment we had 16 different subnets on 16 VLANs, =
using a
Linux server(s) for our DNS and an NT 4 server our DHCP/WINS using VLAN
Tagging. We had a few DUP IP’s back then but most we could track =
down to
a malfunctioning DHCP stack or where a static IP Address was =
implemented. But
for the most part no problems with this design. Everything else worked =
like it
should. </span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span =
style=3D'font-size:10.0pt;
font-family:Arial'> </span></font></p>
<p class=3DMsoNormal style=3D'text-indent:.5in'><font size=3D2 =
face=3DArial><span
style=3D'font-size:10.0pt;font-family:Arial'>After moving the NT4 Lease =
database
to 2000’s world we have had many IP Conflicts. When they first =
started
happening it seemed like it was somewhat random as to what was going on, =
but after
a few weeks of tracking down the problem we have found what seems to be =
causing
the problem. The NT 4, 2000, and XP machines appear not to have the =
problem but
Mac’s (by product of the win9x machines we believe), 95, 98 and =
98se in
particular are seeing the problem. </span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span =
style=3D'font-size:10.0pt;
font-family:Arial'> </span></font></p>
<p class=3DMsoNormal style=3D'text-indent:.5in'><font size=3D2 =
face=3DArial><span
style=3D'font-size:10.0pt;font-family:Arial'>When a 9x machine gets a =
DHCP lease
from the server for the first time both leases are in sync with the 2000 =
DHCP
server. We did a manual release/renew on the 9x machine and the time =
stayed in sync
with the DHCP server. Then we rebooted the 9x machine and noticed that =
the time
became out of sync with the server. So we put a sniffer on the 9x =
machine and
saw the machine issue a DHCP renew at boot that was a broadcast style, =
but with
no response from the server. The NT/XP based machines do a directed =
broadcast
for their renewal of the lease upon boot. We then looked at the server =
and the
leases were even more out of sync. All the while on the client 9 x =
machines it
kept reporting that it had renewed its lease and put the time at which =
it had
attempted to renew in the leases field. The next step was to reboot the =
machine
without a network cable attached. The same thing happened a lease was =
renewed
and no server was contacted. I tried this with a 2000 and XP machine and =
upon
boot the IP protocol doesn’t come up until you have a =
</span></font><font
size=3D2 face=3DArial><span =
style=3D'font-size:10.0pt;font-family:Arial'>Link</span></font><font
size=3D2 face=3DArial><span =
style=3D'font-size:10.0pt;font-family:Arial'> </span></font><font
size=3D2 face=3DArial><span =
style=3D'font-size:10.0pt;font-family:Arial'>State</span></font><font
size=3D2 face=3DArial><span =
style=3D'font-size:10.0pt;font-family:Arial'> on the
network card. After plugging it in to the wall the adaptor got a lease =
and it
was in sync with the DHCP server. What this causes is that the more =
times the
9x machine reboots, or even worse are overnight powered off, machines =
become
vastly out of sync with the DHCP server. After 7 days, which is =
our lease
time here, the DHCP server then removes the lease for the 9x machine and =
then
assigns it to another client. The 9x machine still thinks it has more =
time on
its lease and thus keeps the IP. </span></font></p>
<p class=3DMsoNormal style=3D'text-indent:.5in'><font size=3D2 =
face=3DArial><span
style=3D'font-size:10.0pt;font-family:Arial'> </span></font></p>
<p class=3DMsoNormal style=3D'text-indent:.5in'><font size=3D2 =
face=3DArial><span
style=3D'font-size:10.0pt;font-family:Arial'>We have tired the DHCP =
release on
shutdown hack but it has a very nasty side affect with the 2000 DHCP =
server.
When the user powers the machine on yes their IP is released but the =
machine
still doesn’t do a proper renew upon boot, and the user is forced =
to do a
manual renew, a real problem here! Does anyone know of a fix for the 9x =
client,
or is an upgrade to the OS our only solution?</span></font></p>
<p class=3DMsoNormal style=3D'text-indent:.5in'><font size=3D2 =
face=3DArial><span
style=3D'font-size:10.0pt;font-family:Arial'> </span></font></p>
<p class=3DMsoNormal style=3D'text-indent:.5in'><font size=3D2 =
face=3DArial><span
style=3D'font-size:10.0pt;font-family:Arial'>We also have tried to use =
conflict
detection on the DHCP server but this doesn’t work when the client =
is
powered off over night.</span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span =
style=3D'font-size:10.0pt;
font-family:Arial'> </span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span =
style=3D'font-size:10.0pt;
font-family:Arial'> =
Just to clarify my mind this is how DHCP on a 9x client <u>SHOULD</u> =
work. New
computer on network and no previous leases in its DHCP stack. Upon boot =
it gets
a new address from the DHCP server and its lease time. (Given in an =
offset from
current time on each machine.) The 9x machine is rebooted and it SHOULD =
keep
the same lease time in its DHCP information until it reaches the =BD way =
point
and then attempts a lease renewal. At this time it does a directed DHCP =
renew
to the server listed in its DHCP information and thus extends its lease. =
Also
when a 9x machine is booted without a network cable the DHCP stack =
should come
up with no lease or a Microsoft Automatic Private IP Addresses i.e. a =
169.x.x.x
number.</span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span =
style=3D'font-size:10.0pt;
font-family:Arial'> </span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span =
style=3D'font-size:10.0pt;
font-family:Arial'> </span></font></p>
<p class=3DMsoNormal><font size=3D3 face=3D"Times New Roman"><span =
style=3D'font-size:
12.0pt'> </span></font></p>
<p class=3DMsoNormal><font size=3D3 face=3D"Times New Roman"><span =
style=3D'font-size:
12.0pt'> </span></font></p>
</div>
</body>
</html>
------=_NextPart_000_0024_01C1AA66.2FA51A60--
___________________________________________________
You are subscribed to the ResNet-L mailing list.
To subscribe, unsubscribe or search the archives,
go to http://LISTSERV.ND.EDU/archives/resnet-l.html
___________________________________________________
