Windows 7 machines not getting DHCP IP !!!!URGENT!!!!!!

[mohsinalizai]

We are having a very strange problem , that is we have a lan with 16  vlans and all the vlans have different DHCP for each vlan in the  coreswitch (Cisco 6509) and all the clients in the 16 vlans are windows 7  clients , now the problem is that some machines  are not getting IP Addresses , but if we see the registry settings in  those machines we see that there is an ip address given by the dhcp  server  in the following key of registery

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\Tcpip\Parameters\Interfaces\THE RELATED NETWORK CARD KEY

this ip is not being shown in the network settings instead  APIPA ip 169.245.*.* is shown here ,

DHCP server configuration are check and verified and they are also ok  , packets are also captured which show the whole process of DCHP  request is ok and dhcps in the core switch is replying back with the ip  address to the machines mac address and that same  ip can be seen in the above given registry value.

Kindly help as soon as possible as already alot of time is wasted in tracing this issue.

[cadet alain]

Hi,

Can you post screenshot of ipconfig/all and tcp/ip setting of machine with the APIPA address.

also post sh ip dhcp binding for the IP it should have got on your DHCP server.

Regards.

Alain.

[mohsinalizai]

hi cadetalain

Following are the snap shorts you requested.

[glen.grant]

   The 169 address is the defualt address microsoft assigns when it cannot pull an address  which you say you problem is  .  Make sure portfast is on all user ports .  Verify any trunking is working correctly. between user switches.

[mohsinalizai]

hi glen.grant

yes the Trunbking is ok ,, its fine as i told u that only some pcs in the vlans are having this problem not every pc which makes trunking ok as vlans are working fine , and yes also portfast is enabled even on trunk ports and also verified that no spaning tree or other loop is being generated.

[davidbranka]

Do you have the ip helper address set on each vlan interface with the dhcp server ip address?

Example:

interface Vlan2
ip address 192.168.2.1 255.255.255.0
ip helper-address 192.168.1.100

interface Vlan3
ip address 192.168.3.1 255.255.255.0
ip helper-address 192.168.1.100

[mohsinalizai]

Hi David

I have Configured DHCP server inside the cisco 6509 and all the Vlans are defind in that so no need of giving ip helper in this case.

[cadet alain]

Hi,

Can you do a debug ip dhcp server event and debug ip dhcp server packet while renewing your lease.

At the same time can you sniff on your pc.

Attach all files here.

Regards.

Alain.

[mohsinalizai]

Hi Cadet

Sorry for late reply ,, here are your requested files.

[mohsinalizai]

In these files you can see that wireshark is getiing the same ip for the interface card that is present in the registry where as the tcpip settings is getting APIPA 169.*.*.* ip and in the sniffing captures you can see that dhcp server is assigning the same ip 10.10.10.38 to the request and also in the debug file result is clear that dhcp server i.e cisco 6509 is giving the ip to the mac address , strange thing is this that every setting given by the dhcp server is comming to windows 7 registry  but not to the interface card settings on TCP/IP

[cadet alain]

Hi,

Can you reinstall the tcp/ip stack on the machine.

Regards.

Alain.

[mohsinalizai]

Any Clues ??????? about this abnormal behaviour or may be any mistake that i have done unintentionaaly ???? kindly give your ideas iam really getting lot of  complaints here n my professional integrity  is at stakes

[cadet alain]

Hi,

Can you do what I asked in my previous post.

Regards.

[mohsinalizai]

reset the tcpip stack by

netsh int ip reset

but no change same behaviour.

[cadet alain]

Hi,

uninstall then install not reset and tell me what it gave. Maybe you can also try another firmware for your NIC.

Regards.

Alain.