Vista refuses DHCP offer in the privat IP range??

[Nieuwslezer]

I try to install Vista on a computer in my private network. But the
network interface is not accepting an IP address from the DHCP server.

If on this same hardware I install eg. Linux the PC accepts the offered
IP address from the DHCP server. Imho this rules out a DHCP server
misconfiguration and hardware failure. The IP address assigned is in the
(172.x.x.x) range. On an other computer also installing Vista I see the
same behaviour. On the dhcp server log I see a DHCP request, a DHCP
offer, but no DHCP ack if vista is installed.

If I switch the hardware to a network with public IP addresses and I
install Vista, the system nicely accepts an IP address from the DHCP
server. This rules out hardware/software failure in Vista imho.

My conclusion is that Vista refuses DHCP offers in the private IP
ranges. Has anyone seen this too.

My question is how can I have Vista accept IP addresses in the private
range??

Regards, Koos.

 

[JW]

My Vista accepts private IP addresses in the 192.168.1.xx range from my
Linksys router.

 

[Nieuwslezer]

What netmask do you use? Mine is 255.255.255.192.

Koos.

 

[Dale \Mad_Murdock\ White]

I use a 10.10.10.x address for mine, with a netmask of 255.255.255.0

 

[Kerry Brown]

What netmask do you use? Mine is 255.255.255.192.

Koos.

Try changing the subnet mask to 255.255.0.0 and also 255.255.255.0 to see if
it's a subnet problem. What DHCP server are you using?

 

[Nieuwslezer]

I use fedora core 5 dhcp 3.0.3-28 on both the privat and public netsegment.

At the moment I am reconfiguring the privat network to see if the
standard netmask will work. I believe in the 172.16.x.x range the
"official" netmask is 255.255.0.0. Is this correct???

Koos.

 

[JW]

255.255.255.0

What netmask do you use? Mine is 255.255.255.192.

Koos.

 

[Kerry Brown]

That's correct.

 

[A.J. Werkman]

I changed the netmask to 255.255.0.0. But again the IP address is not
accepted. Again the dhcp server receives a DHCPDISCOVER and sends a
DHCPOFFER and after that all quiet. Vista does not acknowledge the IP
address.

I quess I have to make a temporary network in the 192.168.x.x or
10.x.x.x series and see what happens.

Is there anyone out here who uses Vista with DHCP on a 172.16.x.x net??
What are your experiences??

Koos.

 

[Kerry Brown]

That's a weird problem. Keep us updated on what you find out. It would cause
too much disruption on my network to test it right now. When I get a chance
I'll test it with VMs.

 

[A.J. Werkman]

Got some new information after a few tests.

I put my Vista PC behind a linksys router that hands out IP's in the
range 192.168.1.100/255.255.255.0. Now Vista accepts a IP from the router.

Build up a testlab environment consisting of a linux router with the
ecternal NIC connected to a public IP and internally handing out IP's in
the 192.168.1.100/255.255.255.0 range. Vista does not accept the IP
address here. I use a linux configuration identical to the one described
in my previous message, that is on the public IP net where Vista does
accept a DHCP IP address from the dhcp server. Both routers run dhcpd
3.0.3-28 on Fedora Core 5.

This drives me crazy. One finding makes me think, the problem is in the
dhcp configuration, the other that the problem is in the vista client.

I'll go on testing, I would't mind some help on this issue!!

Koos.

 

[quakechick]

Got some new information after a few tests.

I put my Vista PC behind a linksys router that hands out IP's in the
range 192.168.1.100/255.255.255.0. Now Vista accepts a IP from the router.

Build up a testlab environment consisting of a linux router with the
ecternal NIC connected to a public IP and internally handing out IP's in
the 192.168.1.100/255.255.255.0 range. Vista does not accept the IP
address here. I use a linux configuration identical to the one described
in my previous message, that is on the public IP net where Vista does
accept a DHCP IP address from the dhcp server. Both routers run dhcpd
3.0.3-28 on Fedora Core 5.

This drives me crazy. One finding makes me think, the problem is in the
dhcp configuration, the other that the problem is in the vista client.

I'll go on testing, I would't mind some help on this issue!!

Koos.

do the routers have firewall software within?

 

[Kerry Brown]

It does sound like some sort of incompatibility between the version of dhcpd
and Vista. Quakechick may be on to something. Possibly the Vista firewall
doesn't like something dhcpd is doing. Try disabling the Vista firewall.
Stop the Windows Firewall service and see what happens with ipconfig
/release then /renew.

 

[A.J. Werkman]

In testing I disabled all my firewall settings on the routers.

Firewall problems don't look to me as the source of the problem, because
in a setting where public IP addresses are handed out the DHCP
addresses are accepted by Vista.

The only thing that is consistend with all my data, is that Vista
refuses a dhcp address when there is no direct internet connectivity. I
have my private networks behind routers that do not forward IP packets
and don't have NAT. The linksys router however is configured to do NAT
and therefor is able to reach the outside world. And vista accepts
192.168.1.100 from the linksys router.

I can not see the direct logic in this, because in the process of
getting a dhcp address an OS is not able to communicate outside the
local area network and should not be interested in the outside world at
that stage. But this assumption fits. On the other hand I don't see
cross-network trafic during the dhcp process.

I will look into the vista firewalling.

Can anyone tell me if and how I can follow the DHCP process in Vista?
Can the DHCP process be debugged??

Koos.

 

[Kerry Brown]

I don't see the firewalls on the router as being a problem. The problem
could possibly be the Vista firewall. It could be something in the DHCP
offer packet is slightly different causing the firewall to block it.

Network Monitor 3.0 supports Vista and should help with seeing what is
actually happening from Vista's point of view.

http://blogs.technet.com/netmon/archive/2006/11/22/network-monitor-3-0-has-released.aspx

Capture packets from the Linux DHCP server and from the Vista computer and
compare them. You may also want to capture a successful session with the
Linksys router and compare the DHCP offer packets.

 

[A.J. Werkman]

I have got it!!!!!!!! (Or at least I think I have......)

I build up a testlab consisting of a linux PC that functions as router
and dhcp server. I installed Fedora core 5 out of the box. I defined my
network as 192.168.1.0/24. I configured the dhcp server to hand out ip
addresses in the range 192.168.1.100-192.168.1.200.

After that I started up vista. The IP address offered was not accepted.

Then I changed the the linux PC to handle NAT. This gives the network
PC's the opportunity to reach the outside world. I started up the Vista
PC and it ACCEPTED the ip offer!!!!!

I have no idee what the logic is behind this, but it works like this
overhere.

I would be very pleased if someone here could reproduce this behaviour
of vista. Or can anyone explain this behaviour??

Koos.

 

[Kerry Brown]

We would need to see captures of the packets involved. It sounds like the
DHCP server is doing something different in the two situations. Without
seeing the packets who knows what that difference is. The fault could be
almost anywhere. The DHCP offer could in a non-standard form. The DHCP ack
could be wrong. A firewall somewhere could be blocking things.

 

[cquirke (MVP Windows shell/user)]

On Tue, 13 Feb 2007 08:21:10 +0100, "A.J. Werkman"

I build up a testlab consisting of a linux PC that functions as router
and dhcp server. I installed Fedora core 5 out of the box. I defined my
network as 192.168.1.0/24. I configured the dhcp server to hand out ip
addresses in the range 192.168.1.100-192.168.1.200.

After that I started up vista. The IP address offered was not accepted.

Then I changed the the linux PC to handle NAT. This gives the network
PC's the opportunity to reach the outside world. I started up the Vista
PC and it ACCEPTED the ip offer!!!!!

I have no idee what the logic is behind this, but it works like this
overhere.

I would be very pleased if someone here could reproduce this behaviour
of vista. Or can anyone explain this behaviour??

Guessing here (I'm not a network guru)...

Perhaps Vista doesn't accept a DHCP IP assignment if there's no
gateway IP provided as well?

So that with NAT off, there's no gateway offered via DHCP?

--------------- ---- --- -- - - - -

Saws are too hard to use.
Be easier to use!

 

[A.J. Werkman]

I'll dive into that. See what I can see on the network.

Koos.

 

[A.J. Werkman]

In both situations the default gateway is provided. From that point of
view there is no difference.

Koos.