Vinoth
It would be easier to give you a good answer if you would provide more information about what you are trying to do. But to answer the question based on what we currently have I would say that something is mismatching between the sites - I would check the keys used between the sites, I would check the parameters that are configured for authentication type, for encryption type, I would check for a misconfigured peer address. There is also the possibility that some device (especially a firewall) may not be permitting the VPN traffic.
If you check these things you may find your problem. If you have not found the problem then please provide additional details.
HTH
Rick
HTH
Rick
