Hi Florian,
Thank you for the response.
I had all the mac address in the internal db the issue was user was not getting the ip address.
When i have taken the debug pkt from VC i have noticed the dhcp response was not coming from server .
I informed to check at the DHCP server side then they noticed that pool was full ,they cleared the pool now the users are able to get ip address and able to connect to the network.
Regards,
Mallikarjun