lohithkschalam 92184 (9/6/2016)
As I mentioned above, the SQL server service and SQL server agent is running under same account, I observed from the SQL server error log that the SQL server SPN is being successfully being registered hence there shouldn't be kerbros issue.
The SPN would be only one small piece of the Kerberos process though. The article referenced would still be a good one to work through as there can be numerous reasons for the errors, Kerberos and others. Things such as issues with the account, host file has incorrect or missing local entry, time settings not in sync with AD, Account lacks rights to Access this computer from network and several dozen other possibilities.
Sue