DHCP problem ( Configured on cisco 2610 router )

[abhayaa123]

I are facing problem in DHCP

( Configured on cisco router ). Machines with OS XP are not able to obtain the ip address through DHCP server whereas machines with other OS are able to get the ip address through DHCP.

Can anyone help me in this regards as to what can be the problem and what can be checked at router end.

[a.hajhamad]

You need to check first for those PCs that are not able to get an ip address, assign a static ip address at one of them to check the cabling, and verify using the ping, and also make sure for the duplexing, since i had a problem with a PC that did not get an automatic IP address unless i set the duplex to full instead of the auto.

And also, check the router config:

!

ip dhcp pool POOLXYZ

import all

network X.Y.Z.0 255.255.255.0

dns-server dns-server1 dns-server2

default-router X.Y.Z.1

!

[abhayaa123]

If static ip given the pc works absolutely fine. There are around 200 pc out of which 140 are getting ip address properly from dhcp. Most pc not getting ip are XP.

Event Type: Error

Event Source: Dhcp

Event Category: None

Event ID: 1002

Date: 10/28/2006

Time: 5:45:29 PM

User: N/A

Computer:

Description:

The IP address lease 0.0.0.0 for the Network Card with network address has been denied by the DHCP server 0.0.0.0 (The DHCP Server sent a DHCPNACK message).

For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.

[a.hajhamad]

How many DHCP pools are configured?and did you configure the exclusion?

Try to update the windows XP at one of them.

And also, try to debug the IOS during the DHCP request and also the DHCP server (IOS) reply.

Please note the following note from microsoft:

NOTE: Incorrectly configured split scopes are only one possible cause of a DHCPNACK message.

Thanks

Abd Alqader

[ankbhasi]

Hi Abhay,

Can you confirm that xp and other os machines are in same vlan?

Also can you sniff the switchport on which xp machine is connected to check where the problem is?

Regards,

Ankur